BRIEF COMMUNICATION: The potential of the New Zealand goat industry - Smith RMC; Scholtens MR; Lopez-Lozano SR; Lopez-Villalobos N; Burt D; Harper L; Thomas D; Carr A; Gray D; Tozer P; Schreurs NM (Proceedings of the New Zealand Society of Animal Production, 2017)
The New Zealand goat industry is evolving and there is potential for expansion of its export products. The production and value of the New Zealand goat industry has been explored previously when the industry was in its infancy (Sheppard & O’Donnell 1979), at a time when Mohair production was seen to be ‘the most profitable goat farming enterprise’. Since then major expansion has occurred in the production and export of dairy-goat products, and the production of quality Boer goat meat is under consideration. In order for further progress to be made, knowledge of the current production levels and value of the goat industry, and its potential for expansion is required. Using information describing the current situation of the goat industry (Scholtens et al. 2017) and the value of the goat (Lopez-Lozano et al. 2017), a model was created to estimate the current and potential production and value of the New Zealand goat industry by 2025.

A brief study on the treatment and attitudes to rams on commercial NZ farms - Lee M; Robertson D (Proceedings of the New Zealand Society of Animal Production, 2017)
A study was undertaken to better understand the care and attitudes towards rams on NZ commercial farms. Farms (n=22) were surveyed in Otago and South Canterbury giving indicative data on the treatment and attitudes that commercial farmers have towards rams. On average (SD; Range) the number of ewes put to each ram was, for maternal and terminal sires respectively, 92 (21; 56-143) and 84 (20; 50-100). The reported difference between when rams were put to ewes and when lambs were weaned was 319 days (51; 199-359). Rams were typically put to ewes in April and early May, and weaned as early as November. Visual assessment was most commonly used to assess rams for purchase, with most farmers considering visual attributes and then figures, such as breeding values, to choose rams. The average mortality of rams was reported as 5% (7%; 0-28%). The average culling of maternal and terminal sires over the year was respectively 26 and 29%. Annual health checks by a vet were reported for 45% of the farms. A most common reason for checking was for Brucella ovis testing. This research will provide information to guide further studies on commercial sheep farms.

Calf and heifer development and the onset of puberty in dairy cows with divergent genetic merit for fertility - Meier S; Fisher B; Eketone K; McNaughton LR; Amer PR; Beatson P; Bryant JR; Dodds KG; Spelman R; Roche JR; Burke CR (Proceedings of the New Zealand Society of Animal Production, 2017)
A research herd with divergent genetic merit for fertility was established to better understand the underlying drivers of fertility in dairy cattle. This paper describes the establishment of this herd, heifer growth and development, and the effect of divergence in fertility breeding value (FBV) on the timing of puberty. The average FBV of the high and low fertility groups of heifers was +5.6 and -4.6, respectively. The heifers were weighed fortnightly, with body condition score (BCS) and stature recorded at six, nine, 12 and 15 months of age. Weight and age at puberty were defined as the first day when plasma progesterone was >1 ng/ml in two of three consecutive once weekly samples. There was no effect of FBV on live weight (LWT), BCS, nor stature by age as the heifers matured. High-fertility heifers attained puberty at a lighter LWT (271 vs. 296 kg; SED 4.3 kg), an earlier age (358 vs. 379 days; SED 6.0 days) and a lower proportion of estimated mature LWT (51 vs. 55%; SED 0.7%), compared with Low-fertility heifers. Therefore, the premise that high genetic merit for fertility is positively associated with reaching puberty earlier is supported. Further work is required to support and assess the value of incorporating a puberty trait into the FBV.

Can Raman spectroscopy predict beef meat and eating quality traits? - Fowler SM; Schmidt H; Hopkins DL (Proceedings of the New Zealand Society of Animal Production, 2017)
Quality assurance and guaranteeing meat and eating quality continues to be an ongoing challenge to red meat processors, as many measures of meat quality require resource intensive, destructive or subjective tests. Consequently, there is a need to develop rapid, non-invasive and non-destructive methods for meat quality assessment in commercial processing plants. Therefore, a preliminary investigation was conducted to determine the potential for a hand-held Raman spectroscopic device to predict meat quality and sensory traits measured by an untrained consumer panel. To this end, 45 beef loins (m. longissimus thoracis) were measured using a 671nm hand-held Raman spectroscopic device. Once spectra were collected, loins were frozen until sensory testing and shear force measurements. Further sub-samples were also collected to measure traits including sarcomere length, particle size, pH and colour. Derived models indicate that using Raman spectra it was possible to predict juiciness and tenderness, with cross validated correlations between the predicted and observed values (R2cv) of 0.42 (RMSEP = 11.29) and 0.47 (RMSEP = 10.52). A tentative band assignment suggests that these predictions may be based on changes to the biochemical characteristics of the muscle asso-ciated with hydrophobicity of proteins, fatty acid composition and the collagen matrix. However, further research is required to determine the repeatability and robustness of these models on a larger independent data set.

Changes in rumination behaviour after abrupt or diluted-milk weaning methods in goat kids - Freeman HBR; Webster JR; Zobel G (Proceedings of the New Zealand Society of Animal Production, 2017)
Rumination development is vital during weaning, when kids are transitioning from a reliance on milk to hard feeds. This study analysed rumination behaviour prior to, and following, two weaning methods: abrupt milk removal, and dilution of milk with water; both are common weaning practices on farm. We hypothesised that the dilution weaning method would better prepare kids to cope with the transition to full rumination. Thirty, 13-week-old Saanen cross goat kids were housed in pens of five. Two kids were nominated, for observation, from six pens (n=6/treatment). Kids had free choice access to hay, straw, water and a pelleted ration. Rumination behaviour was continuously recorded for two 24 h periods, before weaning and after weaning. Weaning treatment had no effect on rumination behaviour, though, both daily rumination time and number of boli regurgitated increased following weaning (3.6 vs. 5±0.4 h/d, and 289 vs. 403±29 boli/day). Rumination may be unaffected by using either weaning method, provided the kids have had access to forages and are not weaned too early. Early development of rumination allows kids to cope with milk removal and the switch to solid food, and quantifying its development is important to create best practice guidelines for the weaning period.

A comparison of faecal sample collection times for estimating faecal output and total tract digestibility using inert markers in sheep offered three ryegrass cultivars at two allowances - Jonker A; Cosgrove GP (Proceedings of the New Zealand Society of Animal Production, 2017)
The objective of this study was to compare different faecal sampling regimes (collected in the morning (am) or the afternoon (pm), or the weighted mean of both times) for determining the concentrations of faecal markers (the natural odd-chain n-alkanes (C27 – C35) contained in feed, the dosed (once daily in the morning) synthetic n-alkanes (C32 and C36) and titanium dioxide (TiO2)) and their accuracy for estimating dry matter digestibility (DMD) and faecal dry matter (DM) output from wethers (n = 30) fed cut ryegrasses. The concordance correlation coefficient (CCC) with measured faecal DM output was strong (CCC = 0.8) for faecal DM output predicted from the mean concentration of C32 in morning and afternoon faeces (am+pm), moderate (CCC = 0.6-0.7) when predicted from TiO2 am and am+pm, and weak when predicted from C36. The DMD predicted by C27 and C33 at either collection time, and by C29 and C31 for samples collected in the pm, were similar to measured DMD. The estimated DMD based on faecal C35 had a negligible CCC with measured DMD (CCC<0.1), while other natural n-alkanes had a low to moderate CCC (0.3-0.6) with measured DMD, especially for the samples collected pm and am+pm. For applications with grazing animals, where marker dosing and faecal sampling is often restricted to once daily in the morning for practical reasons, TiO2 was the most accurate marker to estimate faecal DM output and C31 or C33 were the most accurate and precise markers to estimate DMD.

Comparison of health and reproductive treatments over three seasons for once-a-day and twice-a-day milking herds - Van Der Spek P; Sneddon NW; Lopez-Villalobos N; Donaghy DJ; Laven RA; Mueller KR; Amoore J; Doohan H (Proceedings of the New Zealand Society of Animal Production, 2017)
Once-a-day (OAD) milking has been increasing in popularity in New Zealand, while housing cows is being advocated as one means of minimising environmental impacts of dairying. The present study aimed to investigate health treatments under four different farming systems: OAD, and three twice-a-day (TAD) systems (housed, standard and commercial). There were health records from 377 cows milked OAD and 878 cows milked TAD, over the dairy seasons 2013-14, 2014-15 and 2015-16. Data were analysed assuming binomial distributions for the dependent variables with a generalised linear model that included the effects of season, system (OAD, TAD systems), breed and lactation number. In 2014-15, cows milked OAD were treated less often for mas-titis than cows milked TAD (12% and 25% respectively; P<0.05). Cows milked OAD had fewer reproductive treatments compared to cows milked TAD (standard) in 2014-15 and 2015-16 (1% vs 39% and 2% vs 40% respectively; P<0.01). These results support the advice to farmers that milking OAD does not have a major impact on the risk of mastitis but may provide benefits in terms of reproductive performance. In addition, cows milked TAD (housed) had 13% of the cows treated for lameness compared to 7% of cows milked TAD (standard) (P<0.01).

Contract session: An overview of postpartum hyperketonaemia and its association with cow health and performance in pasture-based dairy systems - Phyn CVC; Kuhn-Sherlock B; Turner S-A; Grala TM; Burke CR; Roche JR (Proceedings of the New Zealand Society of Animal Production, 2017)
Following calving, dairy cows undergo a period of negative energy balance during which they mobilise body tissue (such as fat) to support the demands of lactation. When the negative energy balance is severe, the inability of the liver to process all the mobilised fatty acids can lead to hepatic lipidosis (i.e., fatty liver disease) and incomplete fatty acid oxidation. The latter results in the hepatic production of ketone bodies, predominantly β-hydroxybutyrate (BHB), which are released into the circulation as the product of ketogenesis. The increased concentration of ketones in blood is known as hyperketonaemia...

Contract session: BVD bulk milk testing - Lowe AD (Proceedings of the New Zealand Society of Animal Production, 2017)
Bovine Viral Diarrhoea (BVD) is a highly prevalent and infectious viral disease found in cattle in New Zealand, and in many other countries around the world. It is a widespread disease and it is estimated that up to 60% of NZ dairy and beef cows have been exposed to BVD (BVD Steering Committee 2017, http://www.controlbvd.org.nz). The BVD virus (pestivirus) has damaging effects on the health, reproductive performance, growth, and productivity of a dairy herd and sometimes causes death. The production losses are significant; estimated annual losses for NZ dairy farmers are around $127 million. The cost for our beef farmers is around $3000-$9000 per 100 cows in infected herds (BVD Steering Committee 2017, http://www.controlbvd.org.nz). BVD is a serious threat to our farmers, but also to New Zealand’s economy...

Contract session: Caprine arthritis encephalitis in New Zealand dairy goat farms - Pryor SM (Proceedings of the New Zealand Society of Animal Production, 2017)
Caprine arthritis-encephalitis (CAE) is a widespread disease in goats that was first reported in New Zealand in 1981 (Oliver 1982; Oliver et al. 1983). The disease is caused by a lentivirus (CAEV) which, like all retroviruses, inserts its genome into the DNA of the cell it infects. CAEV infects and replicates within monocytes and macrophages and these immune cells then carry the virus throughout the body. Seroconversion typically occurs slowly (months rather than weeks) and there is no simple relationship between the initial infection and moment of conversion. All breeds and ages of goats are susceptible to infection and, once established, it persists throughout the animal’s life. Progression of the disease can take months to years and it is unusual to observe gross clinical signs prior to two years of age. Not all goats that are infected with CAEV will develop the disease and these asymptomatic carriers may spread the disease within the herd. The most common symptom of CAE is chronic arthritis in adult animals. Bilateral or unilateral swelling of the carpal region is common, hence the lay term ‘big knees’. Infection can also lead to weight loss and/or impaired milk production (Greenwood 1995). The major transmission route of CAEV is through the ingestion of virus-infected colostrum by kids, although lateral transmission through prolonged close contact with infected animals is also thought to occur (Adams et al. 1983) and, more recently, evidence suggests that vertical transmission from the reproductive tract of infected females to their offspring is possible (Hasegawa et al. 2017). CAEV has been found in semen, so it is also possible that a doe may get the disease from an infected buck (Souza et al. 2013).

Contract session: Evaluation of the performance of real time PCR for detection of Staphylococcus aureus in dairy cows, using herd test milk samples - Thresher RA (Proceedings of the New Zealand Society of Animal Production, 2017)
Mastitis in dairy cattle is of considerable consequence in NZ, with estimates of over $200 million per annum loss of potential earnings caused by reduction in milk quality and decreased production (Blackwell & Lacy-Hulbert 2012). Somatic cell count (SCC) is used by farmers for udder health monitoring–with an increase in cell count being an indicator of infection. On-farm, monitoring the bulk milk (BM) SCC is used to gauge sub-clinical mastitis infection in the herd. An increase in or a consistently high BM SCC can indicate infection. Herd Testing (HT) provides the individual animal SCC. The Smart SAMM guidelines Seasonal Approach to Managing Mastitis 2011 plan suggests a target for national average bulk-milk somatic cell count of less than 150,000 cells/ml (Woolford et al. 1995), BMSCC exceeding 400,000 cells/ml are subject to dairy company penalties. Individual animal SCCs of over 150,000 cells/ml, or 120,000 cells/ml for heifers, are indicative of an infection...

Contract session: Facial eczema prevention - Cuttance W; Cuttance E (Proceedings of the New Zealand Society of Animal Production, 2017)
Facial eczema (FE) significantly impacts on the health and productivity of cattle (Towers & Smith 1978) and presents significant welfare concerns. The clinical manifestations of FE arise from damage to the liver. When spore count challenges are low to moderate and sustained, low-grade, chronic liver damage can then result in sub-clinical FE, a condition characterised by suboptimal productivity with little or no clinical signs. It is likely that sub-clinical FE goes un-noticed by many herd managers. Whenever there is a significant FE challenge, farmers tend to recognise the presence of disease by identifying photosensitization in individual cows. It is possible for images of affected animals to be made public via animal welfare groups. This presents a risk to New Zealand’s ‘clean green image’ and reputation for sustaining a high level of animal welfare in farmed livestock. However, photosensitisation represents only the tip of the iceberg of a herd-level FE problem. Research has shown that only a small proportion of cows within a herd affected by FE have photosensitisation, with a much greater proportion having significant liver damage without any obvious clinical signs (Di Menna et al. 2009). The causative agent of FE (a fungus, Pithomyces chartarum) was first identified in New Zealand in 1958. Since then protocols for management of the problem have been developed, mostly involving regular administration of zinc (Zn) salts to cattle by mouth. However, over the years a number of alternative management ideas for controlling facial eczema have also been tried and farmers have been discussing these methods with some conviction for years.

Culling reasons in once-a-day milking cows and differences in production and type traits between retained and culled cows - Rocha JF; Lopez-Villalobos N; Burke JL (Proceedings of the New Zealand Society of Animal Production, 2017)
The aim of this study was to investigate the culling reasons in cows milked once-a-day (OAD), evaluating the differences of production, fertility and traits other than production (TOP) between retained and culled cows. Cows in different lactations from Massey University Dairy 1 were scored for 18 TOP for three consecutive seasons from 2013 to 2015. Herd-test records were used to estimate milk yield (MY), fat yield (FY), protein yield (PY) and somatic cell score (SCS). Low fertility, poor udder conforma-tion and low production were the main reasons for culling in all seasons. Overall, culled cows had a lower MY (3534±56 kg), FY (173.5±2.8 kg), PY (138.5±2.1 kg) and higher SCS (6.41±0.09) than retained cows (MY = 4006±41 kg; FY = 204.7±1.9 kg; PY = 160.6±1.5; SCS = 6.19±0.06). Culled cows had a poorer adaptability to milking (7.02 ± 0.04) and poorer farmer’s overall opin-ion (7.62±0.06) than retained cows (7.23±0.03 and 7.89±0.04, respectively). Moreover, culled cows had a weaker udder support (5.56), weaker front udder (5.48) and lower rear udder (6.01) than retained cows (6.19, 5.85 and 6.25, respectively). These traits might have a higher influence on the culling decisions of OAD dairy farms than the age and production worth of cows.

Development of value-added lamb cuts for the modern consumer - Fowler SM; Pethick DW; Hopkins DL (Proceedings of the New Zealand Society of Animal Production, 2017)
As genetics and management practices have improved within the Australian lamb industry, the weight of lamb carcases has in-creased. Yet, the demographics of lamb consumers and their consumption patterns have changed, as household size has become smaller. Consequently, the traditional lamb cuts have less appeal to consumers from smaller households when taken from heavy carcases (>25kg). Therefore, research has been conducted to determine the potential for fabricating new cuts from heavier lamb carcases, determine the nutritional composition of new cuts and examine the impact of increasing carcase weight and fat depths on the time and labour required to process larger carcases into smaller cuts. Development of an information matrix of available lamb data on the eating and nutritional qualities and contribution to total carcase yield highlighted the potential to create further val-ue-added cuts from the forequarter and leg. However, the time taken to fabricate these increasingly value-added cuts from heavier carcases increased with carcase weight (0.44 minutes/kg (s.e. = 0.065) and changes to the saleable meat yield resulted in increased average product prices. Based on the program, a new cut called the Compact Shoulder Roast was developed to provide an option for retailers when processing heavy carcases. This paper outlines some of the outcomes of this program.

Effect of cow body condition score on inter-calving interval, pregnancy diagnosis, weaning rate and calf weaning weight in beef cattle - Tait IM; Morris ST; Kenyon PR; Garrick DJ; Pleasants AB; Hickson RE (Proceedings of the New Zealand Society of Animal Production, 2017)
The aim of this study was to describe the effect of cow body condition score (BCS) on pregnancy rate, inter-calving interval, wean-ing rate and birth and weaning weights of calves. Measurements of BCS in a herd of mixed age (2-10 years), predominantly Angus, beef cows were recorded annually four times between November 2012 and March 2015, at joining/rebreeding (November), wean-ing/pregnancy diagnosis (PD, March), winter (June) and calving (August). Year influenced BCS (P<0.05) and BCS was greatest at weaning 2014. Two-year-old cows had greater BCS (P<0.05) than three-year-old and the mixed age cows. Pregnancy rate was no different (P>0.05) between BCS at calving, joining and PD. Cows that increased BCS from joining to PD had lower pregnancy rate than cows that maintained or decreased BCS during this period, although it is unclear whether this association reflects an influence of BCS on pregnancy rate, or whether the BCS change was a result of differing pregnancy status. Greater BCS at joining was associated with lower calf birth weights. Body condition score at each event was not associated with inter-calving interval or calf weaning weight. Further research is still required to determine the optimum BCS at each stage of the production cycle.

The effect of grazing ewe lambs on lucerne (Medicago sativa) prior to breeding on aspects of reproductive performance - Corner-Thomas RA; Panns JM; Kemp PD; Morris ST; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2017)
Ewe lamb breeding can result in low and variable reproductive performance which is one of the reasons given by farmers for not breeding their ewe lambs. Ewe lamb twinning rates are known to be increased with greater ewe liveweight gain in the weeks leading up to the introduction of the ram. The hypothesis was that offering lucerne for a one-month period that ended 14 days prior to breeding would alter the pattern of breeding (i.e. cycle of conception) and pregnancy and reproductive rates of ewe lambs. Of-fering lucerne had no effect (P>0.05) on the pattern of breeding in both years of the study, respectively. Offering lucerne, however, resulted in a greater percentage of ewe lambs diagnosed with twin-fetuses compared to those offered unimproved ryegrass pastures in 2015 (35% vs. 18%, respectively). In 2016, however, there was no effect of grazing lucerne on reproductive rate. The difference between years was likely the result of lower lucerne masses offered in 2015 than in 2016.

The effect of live weight at weaning on liveweight gain of early weaned lambs onto a herb-clover mixed sward - Ekanayake WEMLJ; Corner-Thomas RA; Cranston LM; Kenyon PR; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2017)
Twin lambs that weighed a minimum of 16 kg (n=134 in 2014 and n=124 in 2015) were randomly allocated to one of three treat-ments: (i) Early weaning (54 and 46 days after the midpoint of lambing in 2014 and 2015, respectively) onto a herb-clover mixed sward (plantain, chicory, red clover and white clover) (HerbEW); (ii) Lambs + dams unweaned on a herb-clover mixed sward until conventional weaning at approximately 13 weeks of age (HerbCW); and (iii) Lambs + dams unweaned on a grass-clover mixed sward until conventional weaning (GrassCW). In 2014, overall greater (P<0.05) liveweight gains were found in HerbCW lambs followed by HerbEW and GrassCW lambs. In 2015, liveweight gains of HerbCW and GrassCW lambs did not differ (P>0.05), but were greater than gains of HerbEW lambs (P<0.05). In 2014, HerbEW lambs that were > 20 kg grew more quickly than HerbEW lambs that were <18 kg (P<0.05). In 2015, HerbEW lambs had similar rate of liveweight gain irrespective of their live weight at treatment allocation (P>0.05). Lambs can be weaned early onto herb-clover mixed swards and achieve greater liveweight gains after wean-ing compared to lambs unweaned on grass-clover mixed sward. Weaning lambs less than 20 kg onto herb-clover mixed sward, however, can result in lower lamb liveweight gain compared to heavier lambs.

The effect of mid-pregnancy nutrition and body condition score on the behaviour of triplet-bearing ewes and their lambs - Gronqvist GV; Hickson RE; Corner-Thomas RA; Stafford KJ; Morris ST; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2017)
Nutrition of ewes during pregnancy may affect the behaviour of ewes and their lambs in the first few days of life. In this experiment, triplet-bearing ewes were allocated ‘medium’ (pasture mass 800-1200 kg DM/ha) or ad-libitum nutrition (pasture mass 1500-2000 kg DM/ha) from day 93 until 114 of pregnancy. Both treatments included ewes of body condition score (BCS) ≤2.0, 2.5 or ≥3.0 as measured on day 92 of pregnancy. Behaviours of ewes and lambs were recorded in the paddock at tagging and a subset of lambs was subjected to a maternal-recognition test. Within the BCS≤2.0 ewe group, lambs born to ewes on the medium treatment emitted more high-pitched bleats and lower low-pitched bleats than lambs born to ewes on the ad-libitum treatment. In the paddock, there was no effect of ewe feeding treatment or BCS group on the median time taken for the lambs to stand, make contact with, suck from or follow their dam. In the maternal-recognition test, the median time taken for the lambs to reach the dam and the time the lambs spent with her was not affected by ewe BCS or feeding treatment. Overall the results indicate that feeding triplet-bearing ewes above pregnancy requirements has minimal effect on lamb behaviours. There is, however, some evidence to suggest that lambs born to ewes in the BCS≤2.0 group offered the medium treatments may have experienced a weaker ewe-lamb bond.

Effect of slaughter age between 5 to 14 months of age on the quality of sheep meat - Mashelea GA; Parker ME; Schreurs NM (Proceedings of the New Zealand Society of Animal Production, 2017)
Pasture-raised lamb is considered the highest-quality sheep meat product while hogget is a downgraded product considered to be of poorer quality. This experiment aimed to investigate the difference in meat quality between sheep slaughtered at 5, 8 and 14 months of age. Objective meat quality was measured on the loin of young Romney rams slaughtered at 5 (n=20), 8 (n=20) and 14 (n=20) months old. The loin meat from 14-month-old sheep was redder (P<0.001), yellower (P<0.001) with higher intramuscular fat (P=0.003) and had a shorter sarcomere length (P<0.001) compared to the meat from lambs slaughtered at 5 and 8 months of age. The peak shear force was highest at 8 months (P<0.001). Meat from sheep slaughtered at 8 months had greater drip loss than those at 5 and 14 months (P<0.01). The results suggest that slaughtering sheep at 14 months could have benefits on eating quality due to an increase in intramuscular fat.

The effect of yard weaning and contact with humans on behavioural reactivity and liveweight gain of beef breed calves - Ramsay BA; Schoorl JAJ; Stayton KM; Cranston LM; Morris ST; Burnham DL; Cockrem JF; Beausoleil NJ; Hickson RE (Proceedings of the New Zealand Society of Animal Production, 2017)
Yard weaning of beef-breed calves is growing in popularity in New Zealand as a way of improving ease of handling, but there is little scientific literature regarding the practice. This experiment examined the effects of yard weaning versus paddock weaning with and without human contact on liveweight gain and behaviour. Paddock-weaned calves lost more live weight in the first sev-en days after weaning (-1.19 ± 0.17 kg/d versus -0.60 ± 0.16 kg/d; P=0.01) than yard-weaned calves but live weight was similar between treatments 42 days after weaning (D42). Yard-weaned calves tended to be less reactive than paddock-weaned calves on D7 (2.16 ± 0.28 versus 2.92 ± 0.33; P= 0.07, where one is least reactive and five is most reactive), but there were no differences in reactivity on D42. Faecal corticosterone concentrations were similar between weaning location, however, calves with minimal human contact had higher faecal corticosterone concentrations 48 hours after weaning than did calves with daily human contact (27.6 ± 2.11 ng/ml versus 18.6 ± 2.11 ng/ml; P<0.01), regardless of location. There were short-term advantages in live weight and heart rate associated with yard weaning of beef-breed calves, but these did not persist to D42.

The effects of early access to meal on the behaviour of artificially reared dairy lambs - Nieper BA; Khan MA; Ganesh S; Knol FW; Peterson SW; Stafford KJ; Stevens DR; McCoard SA (Proceedings of the New Zealand Society of Animal Production, 2017)
he New Zealand sheep dairy industry is growing (Peterson & Prichard 2015). Several large commercial sheep dairy farms remove lambs from their dams within the first four days of life. In some systems, lambs have access to milk replacer (MR) ad libitum and a grain-based solid feed (Bimczok et al. 2005). Compared to young ruminants fed a milk-only diet, early access to solid feed stimulates rumen development (Baldwin et al. 2004) and earlier onset of rumination (Khan et al. 2016) to allow early weaning off MR (Bimczok et al. 2005). Earlier rumen development through access to meal may also encourage earlier grazing of pasture and greater rumination, thereby supporting early weaning. The potential to replace meal with early pasture access as the sole solid feed source to support early weaning has not been evaluated...

Estimates of genetic parameters for direct and maternal genetic effects on weaning weights in Dairymeade sheep - Lopez-Villalobos N; King M; King J; Morris RS (Proceedings of the New Zealand Society of Animal Production, 2017)
Dairymeade is a newly registered breed of dairy sheep in the emerging New Zealand dairy sheep industry. The objective of this study was to estimate heritabilities and genetic correlations for direct and maternal genetic effects on weaning weight, as this trait reflects the genetic ability of the lamb to grow (direct genetic effect), and the genetic ability of the ewe to feed her lambs (maternal genetic effect) and protect them (maternal permanent environment). Records of weaning weight were used from 717 lambs born between 2013 and 2016, with a pedigree of 5091 animals over 11 generations. Average and standard deviation of weaning weight, age at weaning and litter size were 18.1±4.0 kg, 51.5±13.0 days and 2.16±0.7 lambs, respectively. At weaning, ewe lambs were 1.1 kg (SE=0.2 kg, P<0.05) lighter than ram lambs and singleton lambs were 4.1 kg (SE=2.9 kg, P<0.05) heavier than triplet lambs. Estimates of heritability (±SE) were 0.55 (±0.24), 0.24 (±0.17) and 0.28 (±0.13) for direct, maternal and total genetic effects, respectively. The proportion of total variance explained by maternal permanent environmental influences was 0.14 (±0.07). The estimated genetic correlation between direct and maternal genetic effects was ‒0.72 (±0.20). Maternal breeding values can be used to select ewe lambs specifically for milk production.

Field investigation of the iodine status of farms in the North Island of New Zealand - Anderson PD; McGhie DON; Parkinson TJ (Proceedings of the New Zealand Society of Animal Production, 2017)
Over a 10-year period 104 farms in the North Island were attended on a consultancy basis, and of these, 29 farms were identified as having clinical signs associated with iodine deficiency (high peri-natal calf mortality, poor conception rate and/or low pregnancy rate). Mean pasture iodine concentrations (n=24) were 0.28 mg/kg (SD=0.16) (‘adequate’ range: 0.40-0.80 mg/kg). Mean animal plasma inorganic iodine (PII) concentrations (n=17) were 40.6 μg/L (SD=16.28) (‘inadequate’ range <45 μg/L). Marginally low iodine status (20-45 μg/L) was present in 13.5% of farms (14 of 104). The overall average deficit for the farms with low pasture iodine (n=19) was calculated to be 3.0 mg iodine per cow per day. Corrective treatment was computed for each farm and made pri-marily through weekly addition of iodine to the drinking water. Following iodine supplementation, mean animal PII was 60.8 μg/L (SD=19.50), a 50% increase over initial values. For individual cattle, there was a significant reduction in the proportion (73.5% to 23.5%) whose PII was marginally low (P=0.001). Clinical responses in livestock were monitored, and on the iodine supplemented farms there was some evidence for a reduction in peri-natal calf mortality and an increase in conception rates, but the amount of data was limited. Iodine supplementation was seen to contribute to an overall increase in pregnancy rates on ten farms (from 79.4% to 91.1%). It is concluded that iodine deficiency is common in North Island pasture-based livestock farms, that it is responsive to dietary supplementation, and that supplementation may be associated with improved reproductive performance.

Growth curves of New Zealand Holstein-Friesian, Jersey and Holstein-Friesian-Jersey crossbred heifers - Handcock RC; Lopez-Villalobos N; McNaughton LR; Edwards GR; Hickson RE (Proceedings of the New Zealand Society of Animal Production, 2017)
There are differences in the proportion of target live weight (LWT) achieved between the main breeds of dairy heifers in New Zealand, suggesting a potential difference in growth pattern. The objectives of this study were to model growth curves of dairy heifers through random regression of Legendre polynomials, and to compare growth curves of the main breeds. Data comprised of 1,653,214 LWT records obtained from 189,936 dairy heifers in 1,547 herds. The fourth-order Legendre polynomial was the best at predicting LWT, with a relative prediction error (RPE) of less than 4% for the whole dataset and for Holstein-Friesian, Jersey and Holstein-Friesian-Jersey crossbred (F×J) heifers. The regression coefficients of the growth curve differed among breeds for the intercept (α0; P<0.001), linear effect (α1; P<0.001), quadratic effect (α2; P<0.001), cubic effect (α3; P<0.001) and quartic effect (α4; P<0.001). At all ages Holstein-Friesian heifers were heavier than F×J which were heavier than Jersey heifers (P<0.001). The percentage difference among the breeds varied throughout the growth curve, indicating that the main breeds of dairy heifers in New Zealand exhibited different growth patterns that were non-linear. The different growth patterns for each breed should be considered when formulating target LWTs and growth rates.

How does feeding meal affect growth of artificially reared East Friesian-cross dairy lambs? - Jensen AC; Khan MA; Knol FW; Peterson SW; Morel PCH; McKenzie C; Stevens DR; McCoard SA (Proceedings of the New Zealand Society of Animal Production, 2017)
Artificial rearing is routinely used in large-scale dairy sheep farms. One approach is to offer milk replacer (MR) and meal ad libi-tum to lambs. Our aim was to evaluate growth performance of female lambs in the first 12 weeks of rearing with (M) and without (NM) grain-based meal access (n=30/group) during four feeding periods. In period 1 (wk 0-3) lambs were offered MR and meal ad libitum, and in period 2 (wk 4-5) were transitioned outdoors onto pasture with continued access to MR and meal. Lambs were weaned off MR in period 3 (wk 6-10), and meal in period 4 (wk 10-12). The NM lambs received identical management but meal was excluded. A treatment-by-time interaction was found whereby NM lambs had lower average daily gain (ADG) (P<0.05) in periods 1 (376±6 vs. 414±8 g/day) and 3 (146±7 vs. 241±7 g/day), no difference in period 2 (P>0.05), and higher ADG in period 4 (157±18 vs. -55±18 g/day, P<0.05) than M lambs. There was no difference (P>0.05) in live weight by week 12, and all lambs survived. These results indicate when lambs fed MR ad libitum are offered unrestricted access to good-quality pasture before weaning, meal may not be required to achieve a similar live weight at 12 weeks.

Impact of early weaning on rumen fermentation profiles of artificially reared lambs - Cristobal-Carballo O; Khan MA; Knol FW; Lewis SJ; Stevens D; McCoard SA (Proceedings of the New Zealand Society of Animal Production, 2017)
This study investigated the impact of weaning age on rumen fermentation profiles in lambs. Mixed-sex lambs (n=32) were ran-domly allocated to one of two weaning groups: early-weaning (4wk) and control (6wk). Milk replacer (24% CP and 25% fat, DM basis) was offered at 20% of initial body weight. Lambs were weaned at either four or six weeks after commencement of the trial using a three-week step-down procedure, initiated at the start of week 2 (early weaned group) or week 4 (control group). Lambs were individually penned indoors and concentrate and chopped meadow hay were offered ad libitum and individual feed intakes recorded until week six. At the end of week six, lambs were moved onto a ryegrass-based pasture and transitioned to an all pasture diet by week ten. Rumen contents were collected at slaughter, half of the lambs from each group at week four and sixteen, to de-termine rumen pH, and short chain fatty acid (SCFA) and ammonia concentrations. Ammonia concentrations were 132% greater (P<0.05) in early weaned than control lambs at week four, but did not differ at week sixteen. Weaning age did not affect ruminal pH and SCFA total concentrations and proportions at week four or sixteen. The results suggest that ruminal fermentation can be established in lambs weaned off milk by four weeks using a step-down weaning method.

Intramuscular fat content of New Zealand lamb M. longissimus lumborum - Craigie CR; Agnew MP; Stuart AD; Shorten PR; Reis MM; Taukiri KR; PL Johnson (Proceedings of the New Zealand Society of Animal Production, 2017)
The content of intramuscular fat (IMF%) in lamb is an important trait for the lamb-meat value chain. Not only is IMF% an import-ant energy reserve for replacement stock, IMF% is an important driver of lamb-meat eating quality. A growing body of research shows an antagonistic relationship between muscle growth traits and fat content across the lamb carcass (including IMF%). The New Zealand sheep industry has selected for muscle growth traits for decades to improve production efficiency and reduce extremes of carcass fatness historically observed, but the impacts on IMF% levels in New Zealand lamb have not been widely investigated. This paper aims to stimulate discussion on lamb IMF% by reporting on levels of IMF% observed in the M. longissimus lumborum (LL) of 1,705 progeny test lambs raised under extensive, pasture-based production systems across New Zealand, and investigates the relationship between IMF% and carcass weight, VIAscan®-predicted GR (VSGR) and lean-meat-yield percentage (VSYLD). The average IMF% was 2.69%, (SD = 0.83%, and ranged between 0.91-6.42%). IMF% is positively correlated with carcass weight and VSGR and negatively correlated with VSYLD. Considerable variation exists in lamb IMF%, highlighting the opportunity to manage IMF% through genetic improvement and optimised on-farm management.

Mechanical properties of black, grey, and white hoof material of sheep - Scobie DR; Makela AG; van Koten C; O'Connell D (Proceedings of the New Zealand Society of Animal Production, 2017)
A study was undertaken to better understand the care and attitudes towards rams on NZ commercial farms. Farms (n=22) were surveyed in Otago and South Canterbury giving indicative data on the treatment and attitudes that commercial farmers have towards rams. On average (SD; Range) the number of ewes put to each ram was, for maternal and terminal sires respectively, 92 (21; 56-143) and 84 (20; 50-100). The reported difference between when rams were put to ewes and when lambs were weaned was 319 days (51; 199-359). Rams were typically put to ewes in April and early May, and weaned as early as November. Visual assessment was most commonly used to assess rams for purchase, with most farmers considering visual attributes and then figures, such as breeding values, to choose rams. The average mortality of rams was reported as 5% (7%; 0-28%). The average culling of maternal and terminal sires over the year was respectively 26 and 29%. Annual health checks by a vet were reported for 45% of the farms. A most common reason for checking was for Brucella ovis testing. This research will provide information to guide further studies on commercial sheep farms.

Oocyte maturation and quality in dairy heifers with diverse genetic merit for fertility - Reed CB; Meier S; Pitman JL; Burke CR (Proceedings of the New Zealand Society of Animal Production, 2017)
Oestrous behaviour, cumulus cell-oocyte complex (COC) quality, and steroid concentrations were characterised in dairy heifers of high and low values for fertility breeding value (FBV). The hypothesis was that the greater FBV is partly mediated through improved oocyte quality. Ovum pick-up (OPU) was used to collect COCs from the preovulatory follicle of 40 heifers observed in oestrus. Multiplex Taqman qPCR was used to investigate gene expression in cumulus cells (eight genes) and oocytes (three genes) of the recovered healthy COCs (n=9 per group). Plasma and follicular fluid steroid concentrations were measured using high-performance liquid chromatography. Low-FBV heifers were more active in the first eight hours of oestrus (P<0.05), leading to earlier detection and OPU (P<0.05). Consequently, COCs recovered from low-FBV heifers were morphologically less mature (P<0.05) and tended to have lower expression of genes regulating maturation compared with high-FBV heifers. Our findings suggest COC development is retarded in low-FBV heifers relative to the timing of visually observed oestrus, which may result in a poorly developed oocyte at ovulation.

The percentage of spring-calving carryover cows in New Zealand dairy herds and their milk production, compared to heifers, age-matched and lactation-matched non-carryover cows - Gardner RR; Back PJ; Lopez-Villalobos N; McNaughton LR (Proceedings of the New Zealand Society of Animal Production, 2017)
Non-pregnant cows are generally culled from dairy herds and replaced with heifers. Alternatively, non-pregnant cows can be dried-off at the end of lactation, retained for one year (carried over), before being mated and returned to a milking herd in the following year. The aim of this study was to estimate the percentage of spring-calving carryover cows in New Zealand dairy herds and to compare their milk production with that of heifers, lactation-matched and age-matched non-carryover cows. Results showed that 2.5% of spring-calving cows had experienced a previous carryover period. The majority (43%) of carryover cows had failed to conceive during their first lactation. Most (69%) dairy herds contained less than 5% carryover cows and 17% had zero carryover cows. Second-lactation carryover cows produced 4778.1±6.3 L milk, 228.7±0.3 kg fat, 182.0±0.2 kg protein, and had a somatic cell score (SCS) of 6.31±0.01, which was greater (P<0.001) than the milk production of heifers that produced 3514.5±5.9 L milk, 168.3±0.3 kg fat, 134.0±0.2 kg protein, and had a SCS of 5.89±0.01. Carryover cow milk production was also greater (P<0.001) than that of lactation-matched and age-matched non-carryover groups. The results of this study will aid on-farm culling decisions.

Potential anthelmintic properties of urea - Cairns J; McAnulty RW; Greer AW (Proceedings of the New Zealand Society of Animal Production, 2017)
Current gastrointestinal parasite treatment options rely heavily on chemical anthelmintic intervention which targets the nematode residing in the host. However, targeting these organisms during parts of their lifecycle outside the host may also provide a tool for aiding control. In particular, nitrogenous fertilisers produce several potentially toxic compounds, the strategic use of which may affect nematode development. This series of experiments investigated the potential of liquid urea to affect gastrointestinal nematode development. Hatching of Trichostrongylus colubriformis eggs when immersed in liquid urea reduced with increasing urea concentration from 90% at 0% urea to less than 6% in 20% urea solution. This effect was independent of pH and appeared to be nematocidal rather than nematostatic as unhatched eggs failed to hatch following washing and immersion in water. Further, topical application of liquid urea to faeces at a rate equivalent to 200 litres per ha (40 units N) on fresh faeces resulted in a 97% reduction in the number of larvae recovered following culturing compared with equivalent rates of water (P<0.01). Although further studies and refinement are required, these studies indicated targeted application of liquid urea may be a useful tool to assist with parasite control.

Prototype genetic evaluation in a New Zealand dairy sheep flock - Scholtens MR; Peterson SW; Gunson K; Gunson A; Lopez-Villalobos N (Proceedings of the New Zealand Society of Animal Production, 2017)
Dairy sheep milking is an emerging industry in New Zealand, but at present there is no national breeding scheme. A prototype model for the genetic evaluation of dairy sheep was developed. Data were obtained from a flock of 123 crossbred ewes, over 479 monthly flock tests during the season 2015/16. Breeding values were estimated for lactation yields of milk, fat, protein and lac-tose, and for live weight, somatic cell score, first let-down time and yield, and number of lambs born, from a multiple-trait animal model. Heritabilities and phenotypic and genetic correlations required for the model were obtained from the literature, and pheno-typic standard deviations were obtained from the data set. This prototype model to obtain estimated breeding values of animals in this flock can be extended to other dairy sheep farmers, to create selection schemes at industry level and start a systematic breeding program for the emerging New Zealand dairy sheep industry.

Random regression curves for body condition score and live weight from cows in two different dairy systems over three seasons - Sneddon NW; Lopez-Villalobos N; Donaghy DJ (Proceedings of the New Zealand Society of Animal Production, 2017)
As housing is adopted to minimise the environmental impacts of farming activities in New Zealand, it becomes important to investigate the impact of this on the body condition of cows as a predictor of animal welfare. The P21 project undertaken at Massey University’s Dairy 4 recorded the body condition score (BCS) and live weight (LW) of cows either under duration-controlled grazing during sensitive periods (‘housed’) or standard feed-pad (‘standard’) system. A total of 10,350 BCS records and 10,950 LW records were available from 978 cows over three dairy seasons (2013-14 to 2015-16). Random regression curves for daily BCS and LW were modelled using a 5th order Legendre polynomial. Data were analysed with a linear model, which included the effects of system, season, the system by season interaction and proportion of breeds (Jersey and Friesian), and cow age fitted as co-variants. The BCS was greater in 2014-15 than in either 2013-14 or 2015-16, (4.48 vs 4.33 and 4.28, respectively). The BCS of the housed and standard cows were significantly different (P <0.01) in 2013-14 and 2015-16. Housed cows were heavier than standard cows in both 2013-14 and 2014-15. These results indicate that housing of cows could improve on their BCS and LW.

Stand-off pad wintering system: effect of surface types on cow comfort and urination behaviour - Al-marashdeh O; Cameron KC; Bryant RH; Box L; Arends A; Coveney A; Crystal J; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2017)
Two consecutive experiments were conducted over four weeks during winter to investigate the effect of different stand-off pad surface types on dairy cow lying behaviour, cleanness and lameness scores, and urination frequency. In experiment one, 350 Frie-sian × Jersey, pregnant non-lactating dairy cows were blocked and assigned to five treatments for two weeks: fodder beet grazed in situ with no stand-off (control); fodder beet grazed in situ and cows spent 17 hours on a woodchip stand-off (WCG); harvested fodder beet bulb fed in paddock and cows spent 17 hours on a woodchip stand-off (WCH); fodder beet grazed in situ and cows spent 17 hours on a 70 mm round-stone stand-off (S70); fodder beet grazed in situ and cows spent 17 hours on a 50 mm round-stone stand-off (S50). In experiment two, 156 Friesian × Jersey, pregnant non-lactating dairy cows were blocked and assigned to three treatments for two weeks: control and WCG as described in experiment one, and a third geotextile ‘carpet’ stand-off for 17 hours (GC). In experiment one, surface type had no effect on lying time (average 10.1 hours), cleanness and lameness score, or urination behaviour. In experiment two, lying hours were greater (P=0.01) for cows on carpet (11.6) than for cows on woodchip (10.8). While current results showed a negligible effect of surface type on cow comfort and urination behaviour during winter, a longer study, covering the whole winter season, is required to confirm these results.

Validation of an automated system for monitoring water intake and drinking behaviour in dairy calves - Lowe GL; Schütz KE; Sutherland MA; Wilson MT; Stewart M (Proceedings of the New Zealand Society of Animal Production, 2017)
The provision of palatable drinking water ad libitum for cattle is often neglected on farm and is considered difficult and imprac-tical to monitor, particularly on an individual animal basis. The objective of this study was to validate an automated system for monitoring individual water intake and drinking behaviour of dairy calves. Nineteen dairy calves were observed over five days for eight hours/day. Calves were individually identified as they visited a water trough within a narrow chute where the number and duration of visits were recorded using an overhead photoelectric sensor, and water intake was recorded using a flow meter. Data from the automated system were compared to behavioural observations from video recordings across the same time period. The automated system was highly correlated with behavioural observations for both the number of visits (R2=0.96, P<0.001) and visit durations (R2=0.94, P<0.001), but showed no correlation for water intake (R2=0.01, P>0.1). This system could be used as a reliable automated method for recording drinking behaviour in terms of the number and duration of visits. However, alternative systems for measuring water intake need to be investigated and incorporated into the automated system. This information could be used to investigate a number of questions regarding water use and quality, and their effects on calf health and welfare and could be integrated into other automated systems used on farm for daily animal monitoring.

Valuing improved deer genetics - Ward JF; Thompson BR (Proceedings of the New Zealand Society of Animal Production, 2017)
New Zealand deer breeders have made rapid genetic progress in growth traits over the previous decade. A farm-systems analysis was performed using real growth data, to compare sires of differing breed-type and genetic merit for growth traits. Scenarios used red deer maternal sires, of average or high genetic merit, and wapiti terminal sires of high genetic merit. The base scenario of all average-genetic-merit maternal sires was compared against all other systems. Capital stock numbers were adjusted to maintain starting winter pasture covers and total average pasture covers to be as similar as possible; all other core parameters were kept consistent. All high-growth merit scenarios were 6.1%-8.4% more profitable. Median age to slaughter decreased by between 37-61 days, resulting in an increase in average sale value ($/kg) of 5.5%-7.7%. Average carcass weights increased by 2.7%-4.2% with an increase in efficiency (kg product/kg DM consumed) of 1.6%-3.1% over the base scenario. These gains in productivity, profit-ability and efficiency, relative to the base scenario were all achieved with reductions of between 5.6% and 8.0% in the capital hind base. This farm-systems analysis demonstrates that there are favourable gains to be made by deer farmers investing in genetics for improved growth traits.

The welfare of bobby calves sent for slaughter: a synopsis of the science literature within the context of New Zealand’s export system and the problems and gaps in it - Fisher MW; Wild RJ; O'Grady KR; Guigou MJ; Diesch TJ; Jamieson JV; Ward LJ; Cross NJ (Proceedings of the New Zealand Society of Animal Production, 2017)
Most neonatal animals are healthy and vigorous but vulnerable, particularly during the first week of life, to hypothermia and starvation, infections and injuries, and predation. Information collated from the scientific literature and routine ante-mortem in-spections indicates that the main factors predisposing bobby calves to death or condemnation are inadequate colostrum/feeding, and immaturity. Correct feeding regimes and transport protocols can minimise welfare compromises to healthy calves and most presented for slaughter were found to be strong, alert and well fed. However, small numbers of immature, weak, sick and injured calves were also presented. Dead or moribund calves had digestive tract disorders, umbilical infections or were undiagnosed. No curd in the rumen and immaturity were common secondary findings. What is less understood is the degree of hunger bobby calves may experience; the interaction between age/maturity, husbandry, feeding practices, transport and lairage; the limits of feed depri-vation in ‘marginal’ calves; compromises to welfare amongst those animals which do not die or are condemned prior to slaughter; and the impacts of any procurement and processing requirements for periods in lairage.

BRIEF COMMUNICATION: A physiological evaluation of the efficacy of pain-mitigation strategies for cautery-disbudded goat kids - Hempstead MN; Stewart M; Sutherland MA (Proceedings of the New Zealand Society of Animal Production, 2016)
Cautery disbudding is a painful procedure commonly performed on-farm to destroy the horn bud cells of goat kids to prevent horn growth. Disbudding is performed because horns can injure pen mates and stock people. Globally, standard practice of disbudding typically excludes the use of pain-mitigation and there are few studies investigating kid responses to disbudding and different pain-mitigation strategies. To date, pain-mitigation strategies used when disbudding kids include administration of non-steroidal anti-inflammatory drugs (NSAIDs), local anaesthesia (LA) and general anaesthesia (GA). Meloxicam (NSAID) reduced pain-related responses in cautery-disbudded kids (Ingvast-Larsson et al. 2011). Local anaesthetics (e.g., lignocaine), however, have not shown to be affective at reducing the pain response following disbudding (Alvarez et al. 2015). General anaesthesia has been used in kids, but its effect on pain-related responses was not assessed (Ingvast-Larsson et al. 2011). The objective of this study was to evaluate the physiological response to different painmitigation strategies for cautery-disbudding in goat kids.

BRIEF COMMUNICATION: Ad libitum fodder-beet and pasture beef-finishing systems – intake, utilisation, grazing behaviour and liveweight gains - Saldias B; Gibbs SJ (Proceedings of the New Zealand Society of Animal Production, 2016)
Traditionally, New Zealand (NZ) beef-production systems rely almost solely on pasture production. However, the seasonality of pasture growth, which affects quality and quantity, impacts the productivity of the system, with mean slaughter age of 26-36 months. In accelerated beeffinishing systems internationally, cereal grains are used to maintain energy intakes across the production cycle, at a lower cost than is possible in NZ. A recent NZ development in beef-production systems involves ad libitum intakes of fodder beet (FB; Beta vulgaris) with minimal supplement for 130 d from weaning to spring, and then 90 d of grazing on grass-based pasture before slaughter. This system, developed by Gibbs at Lincoln University, allows finishing of spring born animals at 12-18 months of age (Gibbs et al. 2015; Gibbs & Saldias 2014a). Ad libitum intakes after appropriate transition to FB are critical to system profitability, and prevention of rumen acidosis (Gibbs & Saldias 2014b). However, previous NZ crop-feeding experience with brassicas suggests that increased intakes require reduced utilisation of feed (Rugoho 2013). There is no published information on FB utilisation in ad-libitum systems, where high pasture residuals at 24 h post-allocation are used to ensure maximal intakes. Therefore, this study was designed to determine utilisation, grazing behaviour and intake patterns, and liveweight (LWT) gains, in steers grazing FB and then spring perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) based pasture.

BRIEF COMMUNICATION: An investigation of automated measures for assessing pain-induced distress in dairy calves - Sutherland MA; Lowe GL; Huddart FJ; Stewart M (Proceedings of the New Zealand Society of Animal Production, 2016)
Dairy calves are routinely disbudded using hot-iron cautery without pain relief in New Zealand, and studies have shown this procedure causes physiological and behavioural changes indicative of pain (Stafford & Mellor, 2011). To evaluate the effectiveness of different pain mitigation strategies during routine husbandry procedures (e.g., disbudding), intensive physiological and/or behavioural studies are needed. The limitations of these measures are that the methods (e.g., blood sampling) can cause animal stress and analysis of behaviour video recordings is labour intensive. Automated, non-invasive measures of behaviour are now available, such as feeding behaviour provided by automatic calf feeding systems (ACF) and activity, recorded using accelerometers (e.g., Hobo data loggers). Feeding and lying behaviours are altered in calves in response to stress and/or pain during procedures such as hot-iron cautery disbudding (Graf & Senn, 1999; Bates et al. 2015). It is well documented that this procedure causes significant pain. Therefore, the aim of this study was to determine if behavioural data collected from ACF and Hobo data loggers could be used as an indicator of paininduced distress in dairy calves.

BRIEF COMMUNICATION: An update on genetic parameters for facial eczema tolerance in sheep - Mcrae KM; Cullen NG; Amyes NC; PL Johnson (Proceedings of the New Zealand Society of Animal Production, 2016)
Facial Eczema (FE) is a metabolic disease resulting from liver and bile-duct damage, caused by ingestion of the mycotoxin sporidesmin A, found in the spores of the fungus Pithomyces chartarum. Risk of FE is associated with temperature, humidity and dead leaf matter (Mitchell et al. 1959; Brook 1963; Di Menna & Bailey 1973). While FE is predominantly prevalent in the North Island of New Zealand, climatic change projections indicate that there will be an increase in the geographical spread of the fungus and associated sporidesmin, resulting in FE spreading to regions that are currently unaffected (Dennis et al. 2014). Clinical FE is characterised by photosensitisation due to liver injury; however, reduced production (Smith 2000) and reproduction (Moore et al. 1983; Mcmillan et al. 1988; Morris et al. 1991) is also observed in both clinically and sub-clinically affected animals. The heritability of liver damage at slaughter post-sporidesmin challenge was estimated to be 0.42 ± 0.09 (Campbell et al. 1981). In the live animal, serum gamma glutamyltransferase (GGT) collected 2 to 3 weeks after sporidesmin challenge can be used as a measure of liver damage (Towers & Stratton 1978). Romney FE selection lines, initially selected for resistance or susceptibility on the basis of liver damage, were established in 1975...

BRIEF COMMUNICATION: Days to calving and intercalving interval in beef and dairy-beef crossbred cows - Morris ST; Hickson RE; Martin NP; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2016)
One important attribute of a beef-breeding cow is the ability to wean a calf every year. Furthermore, an earlierborn calf is likely to be heavier at weaning and its dam has more opportunity to conceive again during the following breeding season. In a spring-calving system under the seasonal pastoral-grazing system in New Zealand, a 365- day intercalving interval is desirable. A normal gestation length is 280 days leaving 85 days for a cow to resume oestrous cycles and conceive again to maintain the 365- day calving interval. Literature estimates of the interval between calving and the first oestrous cycle post-calving are 53-82 days for mixed-aged beef-breeding cows and 81-95 days for first-lactation beef-breeding cows (Hickson et al. 2012; Knight & Nicoll 1978; Morris et al. 1978; Smeaton et al. 1986), indicating that a 365-day calving interval is difficult to maintain.

BRIEF COMMUNICATION: Do different grazing strategies affect pre-weaning calf growth rates? - Back PJ; Hickson RE; van Bouwel K; de Cock H; Verdurmen J; Sneddon NW; Laven RA (Proceedings of the New Zealand Society of Animal Production, 2016)
Rearing replacement heifer calves is a labour-intensive and expensive component of dairy systems (Drackley 2008). Large numbers of replacement heifers are not meeting target live weights in New Zealand (McNaughton & Lopdell 2012) which has implications for future milk production, fertility and subsequent longevity in the herd (Van Amburgh & Tikofsky 2001). This paper reports results from the second year of a long-term experiment being conducted at Massey University that examines the impact of colostral status and liveweight gain of heifer calves fed different diets on subsequent milk production, fertility and longevity in the herd. Previous work (Cardoso et al. 2015) demonstrated no difference in pre-weaning liveweight gain of calves fed different levels of milk. The calves in that study ate surprisingly little meal. It was surmised that the exposure to frequent shifts onto fresh pasture stimulated intake of pasture, and removed the advantage of feeding calves higher levels of milk and supplementation with meal. Anecdotally, many calves when removed from rearing sheds to pasture are kept on the same paddocks as they are not a high priority for pasture allocation. Therefore, the aim of this experiment was further collection of colostral and Brix data as described by Coleman et al. (2015), and to compare pre-weaning growth rates of calves that are continually offered fresh pasture to those that are set stocked.

BRIEF COMMUNICATION: Does Viagra protect fetal lambs against maternal pregnancy toxaemia? - Peterson SW; Pain SJ; McCoard SA; Oliver M; Baker PN; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2016)
Poor fetal growth is commonly caused by placental insufficiency. In sheep, multiple fetuses have relatively small placentae with fewer cotyledons than singletons, limiting blood flow to the placenta, especially in late gestation when fetal growth rate is highest. Factors that reduce fetal growth, such as maternal genotype, nutrition, age, parity, fetal number, or environmental temperature, typically reduce placental size and are associated with lower rates of fetal oxygen and nutrient uptakes and placental blood flow (Reynolds & Redmer 2001). Further, circumstances that influence placental vascular development have a dramatic impact on fetal growth and development, and affect neonatal survival and growth (Borowicz et al. 2007; Satterfield et al, 2010). Sildenafil citrate (SC, trade names Viagra or Avigra) increases vasodilatation of uteroplacental vessels (Wareing et al. 2005) and may represent a novel therapy to improve fetal lamb growth. Sildenafil citrate has successfully increased birth weight in rodent models and singleton bearing ewes (Satterfield et al. 2010; Miller at al. 2009). There is no published information regarding the use of SC in multiple-bearing ewes. The objective of this trial was to determine if SC administration to triplet-bearing ewes in late gestation could increase lamb birth weight. In addition, the influence of SC on the incidence of pregnancy toxaemia is also reported here.

BRIEF COMMUNICATION: Feed value of maize silage in New Zealand - a review - Kleinmans JJ; Densley RJ; Hurley T; Williams ID; Calbert F (Proceedings of the New Zealand Society of Animal Production, 2016)
Maize silage is a major dietary component for dairy cows in the USA and Germany with average feeding rates of 2.7 and 4.1 tDM per cow per year respectively (Table 1). Maize silage usage in NZ has increased over the past two decades. It currently accounts for approximately 6% of feed energy supplied to the national herd, calculated using national herd energy requirements (based on cow numbers and milk processed 2013/14 in NZ (New Zealand Dairy Statistics 2013/14)) and the amount of maize silage harvested (AIMI 2015). It is important to establish maize silage feed quality in NZ to better understand its potential to support pasture based farms. Published NZ research has measured in-vivo digestibility of maize silage in animal trials (Kirley 1977; Smith 1973); however, the number of trials is limited and they were not performed using standard protocols to allow pooling of data. The aim of this paper was to compare the nutrient composition of overseas and NZ maize silage to determine if overseas in-vivo energy measurements are applicable to local maize silage and to determine how well NZ maize silage kernel is processed.

BRIEF COMMUNICATION: Immediate removal of dairy goat kids from the doe as a strategy to manage colostrum intake - Zobel G; Tan BL; Deeming L (Proceedings of the New Zealand Society of Animal Production, 2016)
An impeded transfer of antibodies between the maternal and fetal circulatory system results in goat kids lacking immunity at birth (Hurley & Theil 2011). The dam’s colostrum, which supplies energy, nutrients and growth hormones, also passively provides immunity via immunoglobulin G (IgG) (Hurley & Theil 2011). Without colostrum, morbidity and mortality increases (O’Brien & Sherman 1993). Unfortunately, colostrum is also a source of disease, such as caprine arthritis-encephalitis (CAE) (Reina et al. 2009). Therefore, removal of the offspring prior to maternal colostrum transfer is often practiced (Reina et al. 2009) because it allows for feeding alternative, disease-free colostrum. For goats, colostrum alternatives include: bovine, heat-treated caprine, and artificial bovinebased replacer. While incorrect heat-treatment can reduce IgG content (Tyler et al. 2000) and some artificial replacers fail to improve immunity acquisition (Constant et al. 1994), few adverse effects (e.g. reduced kid survival) of these alternatives have been noted (MacKenzie et al. 1987; Moretti et al. 2012). Worldwide, farmers are attempting kid removal and alternative colostrum feeding, but it is not known to what extent this practice occurs, nor how successful farmers are at preventing colostrum ingestion from the doe. Since bovine and caprine IgG can be measured in serum, presence or absence of either can help determine the colostrum type ingested. Therefore, the objectives of this study were to: 1) determine the prevalence of immediate kid removal, and 2) compare the farmer-reported percentage of kids successfully removed to the percentage of kids with caprine serum IgG (an indicator of doe colostrum ingested).

BRIEF COMMUNICATION: Impact of date of birth recording practises in genetic evaluation in New Zealand sheep - McIntyre S; Newman S-AN (Proceedings of the New Zealand Society of Animal Production, 2016)
Accuracy of selection is an important feature for all breeding programs and genetic evaluation systems, with genetic gain influenced by the accuracy of the breeding values and by the selection decisions taken by the breeder. Accuracy of estimated breeding values (eBVs) are affected by the amount and quality of the pedigree and performance data recorded. With increasing use of breeding values based on across–flock analyses, the impact of various data recording practises used in sheep flocks needs investigation to ensure practises by any particular breeder do not adversely affect the whole analysis.

BRIEF COMMUNICATION: Plasma amino acid profiles of lactating dairy cows fed fodder beet and ryegrass diets - Pacheco D; Waghorn G; Dalley DE (Proceedings of the New Zealand Society of Animal Production, 2016)
In pastoral systems, N intake by dairy cows generally exceeds requirements (Kolver 2000). Feeds with low N concentration can ‘dilute’ the amount of N eaten by grazing dairy cattle, and ultimately reduce N pollution of the environment. Use of fodder beet (FB) crop has increased substantially in New Zealand because of its high DM yield potential. Fodder beet also has low N content in the bulb of the plant (0.8 to 1.5% of DM; Heuzé et al. 2015) which is useful for diluting dietary N content. However, these low N concentrations could result in deficiencies of specific amino acids (AA), potentially limiting milk production. This paper reports the effect on plasma AA concentrations of partial replacement of ryegrass pasture with FB in the diet of lactating dairy cows. This information will provide insights on how low-N diets could impact nutrient supply to dairy cattle.

BRIEF COMMUNICATION: Preliminary estimates of genetic parameters for adult dag scores in New Zealand sheep and their relationship with juvenile measurements - Mcrae KM; Dodds KG; Newman S-AN; Brito LF; Pickering NK; McEwan JC (Proceedings of the New Zealand Society of Animal Production, 2016)
The accumulation of faecal material around the breech area of sheep (dags) is of interest to the New Zealand sheep industry for a variety of reasons, including financial penalties for presenting animals with dags at slaughter, reduced wool value, increased risk of flystrike and the labour cost associated with dagging both lambs and adult ewes (Pickering et al. 2012). Currently, dag scores at both three (DAG3) and eight (DAG8) months of age are routinely measured, and analysed in Sheep Improvement Limited (SIL). However, there are currently no formally published estimates of the genetic relationship between dag score as a lamb and dag score as an adult (DAGA) in the New Zealand sheep population. Adult dag score has been found to be highly repeatable between 12 months to two years of age (R = 0.42) and between two and three years of age (R = 0.44) in different strains of Merino sheep (Larsen et al. 1995). Currently within SIL, the estimated breeding values (EBVs) calculated from DAG8 measures are reported as the adult dag score EBVs. There are now, however, multiple flocks recording adult dag score in the SIL database. An analysis of the correlation of adult dag score with DAG8 and DAG3 would confirm if the current SIL model is appropriate for reporting adult dag EBVs, or if the model needs revising to include adult dag measures and its correlations with DAG3 and DAG8.

BRIEF COMMUNICATION: The effect of milk allowance on performance of dairy calves - Rosenberger K; Costa JHC; Neave HW; vonKeyserlingk MAF; Weary DM (Proceedings of the New Zealand Society of Animal Production, 2016)
Restricted milk diets increase and hasten the onset of solid feed intake in milk-fed calves (de Passillé et al., 2011) and facilitate the weaning of calves, which reduces the growth check during weaning in comparison to ad libitum fed calves (Huuskonen & Khalili, 2008). As a consequence, dairy calves are commonly fed a restricted milk allowance of approximately 10% of a calf’s BW (approximately 4 to 6 L of milk/d; e.g. Vasseur et al., 2012). However, calves fed a restricted amount of milk (10% of BW) show increased behavioural signs of hunger like non-nutritive visits to the milk feeder (Rushen & de Passillé, 1995) and less growth pre-weaning when compared with calves fed more milk (Khan et al., 2007). Indeed, a growing body of research has consistently shown that calves fed more milk exhibit greater BW gains before weaning (see review by Khan et al., 2011). The aim of this study was to identify the effect of feeding 6 or 12 L/d of milk on average daily gain (ADG) and final body weight (BW) after weaning when using a gradual, step-down weaning method.

BRIEF COMMUNICATION: The use of farm-management tools by New Zealand sheep farmers: changes with time - Corner-Thomas RA; Kenyon PR; Morris ST; Ridler AL; Hickson RE; Greer AW; Logan CM; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2016)
The utilisation of farm-management tools by New Zealand sheep farmers can support on-farm decision making, thus facilitating improvements in productivity and profitability of the farming enterprise. There are numerous management tools available to farmers, for example, a recent report identified 127 tools that were available to New Zealand farmers (Allen & Wolfert 2011). Although a large number of tools are accessible to farmers, a survey of sheep farmers conducted in 2012 by Corner-Thomas et al. (2015) identified many that were utilised by only a small percentage of farmers. This indicates that there is the potential for increased uptake of management tools which, if relevant, may lead to benefits in on-farm productivity. The aim of the current study was to determine for sheep farmers in New Zealand, if use of farm-management tools had changed over a two-year period.

BRIEF COMMUNICATION: The use of infrared thermography and feeding behaviour for early disease detection in New Zealand dairy calves - Lowe GL; Schaefer AL; Wilson MT; Sutherland MA; Stewart M (Proceedings of the New Zealand Society of Animal Production, 2016)
Neonatal calf diarrhoea (NCD) is a disease impacting livestock industries economically and in terms of animal health and welfare. In New Zealand, the most prevalent pathogens associated with NCD are rotavirus and Cryptosporidium (Mawly et al. 2015), but other common pathogens include coronavirus and Salmonella. By the time an animal presents with clinical signs of disease, much of the associated tissue damage to the intestinal submucosa may have already occurred, hence affecting production. Therefore, there is a need to develop methods for early disease detection, which ideally could be incorporated into automated systems for real-time, remote sensing. Infrared thermography (IRT) is a non-invasive method of detecting radiated heat. The use of IRT in livestock and veterinary applications was reviewed by Luzi et al. (2013). Studies have shown IRT can be used for early identification of calves with BRD (bovine respiratory disease) and BVD (bovine viral diarrhoea), using changes in eye temperature (Schaefer et al. 2004, 2012). Schaefer et al. (2012) demonstrated that images could be collected automatically at a water trough. In dairy calves, the behavioural information (e.g. number of visits) gathered remotely at an automatic calf-feeding (ACF) system can be used for identification of at risk animals (Svensson & Jensen, 2007; Borderas et al. 2009). However, the use of these automated systems has not been fully investigated under New Zealand conditions, where calves are exposed to different pathogens and management.

BRIEF COMMUNICATION: Variability in growth rates of goat kids on 16 New Zealand dairy goat farms - Deeming LE; Beausoleil NJ; Stafford KJ; Webster JR; Zobel G (Proceedings of the New Zealand Society of Animal Production, 2016)
Average daily weight gains (ADG) in early life are associated with health, welfare and future production potential of dairy animals. While this has yet to be established for goats, research in cows demonstrates a positive relationship between growth in early life and milk production (Shamay et al. 2005, Soberon et al. 2012). Early growth rates are largely determined by the management practices from birth onwards. It is therefore unsurprising that large differences in ADG under different management systems have been reported. In lambs, Mahgoub et al. (2000) reported a large range in ADG (84-154 g/day). Similarly, in calves, Bartlett et al. (2006) reported ADGs ranging from 251 g/day to 703 g/day. The ADGs reported in goats have not been as variable (152-170 g/day: Galina et al. 1995; 167-173 g/day: Goetsch et al. 2001); however, these were small, controlled studies. To our knowledge, no research has yet quantified variability in the ADG of goat kids on a large, multi-farm scale. Therefore, the aim of this study was to describe the variation in growth rates on multiple dairy goat farms in the Waikato region of NZ, providing a benchmark for dairy goat farmers.

BRIEF COMMUNICATION: Which traits best predict ewe performance and survival the following year on a UK hill farm? - Wishart HM; Lambe NR; Morgan-Davis C; Waterhouse A (Proceedings of the New Zealand Society of Animal Production, 2016)
Increasing ewe longevity and reproductive output can improve whole-flock efficiency and reduce environmental impact (Jones et al. 2013). By increasing ewe longevity (the length of productive life), fewer replacements are required, reducing the number of unproductive animals and increasing the number of ewe lambs to sell (Dickerson & Glimp 1975). Longevity research often looks for genetic indicators of this trait; however, heritability is low, or occasionally moderate (Mekkawy et al. 2009). An alternative approach may be to alter how animals are retained for breeding the following year, allowing animals to reach their potential and not reducing longevity by selling animals that are still productive. To achieve this, it is essential to be able to identify ewes that will survive and be productive. Although most research on longevity concentrates on the whole lifetime of an animal, it may be informative to consider factors that affect just the following years’ performance, in order to aid retention decisions, particularly when genetic information is unavailable.

DEERSelect – review of the first decade - Ward JF; McIntyre SB; Newman S-AN; Asher GW (Proceedings of the New Zealand Society of Animal Production, 2016)
DEERSelect, the New Zealand deer industry performance recording system, has been operating since 2005 in red deer. Over that period, the role and functionality of DEERSelect has grown, such that it is now central to all genetic information delivery to the industry. Initially velvet and growth trait modules were included, with meat and reproduction trait modules added later. Economic indexes were also developed, but have not been widely utilised. Evaluations were added for wapiti, to provide for all breed types. Current desires are for wapiti and red deer to be combined in a single evaluation. Good genetic gains have been made, primarily in growth traits. Impetus provided by the Deer Progeny Test (DPT), and increased breeder education has improved understanding of best practice recording, leading to better data quality and herd connectedness. While DEERSelect is recognised by industry leaders as being critical for genetic advancement, it still has limited stag-buyer adoption. Improved adoption will require a large extension effort so commercial producers can interpret the impacts of breeding values in terms of changes in farm system performance and profitability. The future is promising, with new traits, improvements on existing ones and breeders now valuing objective measures of genetic merit.

Development and evaluation of a temperament-scoring system for farmed deer: genetic and environmental components - Schütz KE; Ward JF; Cox NR; Asher GW (Proceedings of the New Zealand Society of Animal Production, 2016)
A temperament-scoring system for farmed red deer was developed and evaluated. Hinds (n=1102) and their progeny (n=1609) from three farms were repeatedly scored (7867 observations in total) for aggression, agitation in a pen or when confined in a crate, ease of handling, and exit speed from a crate. The animals were scored when yarded for management procedures by one handler. Inter-observer reliability recorded on a separate occasion was between 70 and 82%, measured as percentage agreement. For progeny, heritability was for aggression:0.03±0.024, agitation (pen):0.23±0.077, agitation (crate):0.17±0.056, ease of handling:0.10±0.037, and exit speed:0.04±0.021, with a repeatability of 0.19±0.018, 0.24±0.022, 0.25±0.017, 0.24±0.015, and 0.17±0.013, respectively (estimate±SE of estimate for all preceding values). For hinds, repeatability was for aggression:0.23±0.048, agitation (pen):0.16±0.068, agitation (crate):0.38±0.052, ease of handling:0.45±0.048, and exit speed:0.27±0.061 (estimate±SE of estimate), respectively. Animals that were agitated in a pen were also more agitated in a crate (r=0.352 and 0.479 for progeny and hinds, respectively), all other associations were weak (r≤0.228). Farm, year born, age, and drafting order, but not sex, influenced most temperament scores. Temperament of red deer can reliably be scored in a yard. Agitation showed a moderate genetic component and could, therefore, be included in future breeding programmes.

Dietary preference of dairy cows for perennial ryegrass cultivars growing with and without white clover - Chen A; Bryant RH; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2016)
Dietary preference of dairy cows for eight perennial ryegrass cultivars (AberMagic, Alto, Base, Bealey, Commando, Kamo, One50 and Prospect) growing with and without white clover was examined at two vegetative stages (May and October) and one reproductive stage (November). Groups of dairy cows (n = 8) were offered free choice among cultivars growing with or without white clover for 6 to 8 hours. Preference was defined as the relative decreasing rate in sward surface height. Preference was higher for the tetraploid cultivars, Base and Bealey and the high-sugar diploid cultivar, AberMagic (preference ranged from 1.02 to 1.45). Preference was negatively correlated with herbage mass (r = -0.179, P = 0.013), proportion of dead material (r = -0.301, P < 0.001) and neutral detergent fibre (r = -0.287, P < 0.001), and positively correlated with sward surface height (r = 0.386, P < 0.001), ryegrass lamina length (r = 0.233, P = 0.001), tiller mass (r = 0.338, P < 0.001), water-soluble carbohydrate concentration (r = 0.143, P = 0.049) and organic matter digestibility in dry matter (r = 0.312, P < 0.001). Although the proportion of white clover was low (< 7% DM) in all three experiments, the interactions between perennial ryegrass cultivar and the presence of white clover were significant (P = 0.004 at pre-heading stage, P = 0.046 at reproductive stage and P = 0.038 at post-heading stage), with differences among preference for perennial ryegrass cultivars reduced when white clover was present

Does ewe nutrition during pregnancy affect the neonatal behaviour of twin-born lambs? - Gronqvist GV; Hickson RE; Corner-Thomas RA; Kenyon PR; Stafford KJ; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2016)
In this experiment the effects of feeding treatments from mid pregnancy until lambing on the behaviour of twin-bearing ewes and their lambs were investigated. Fifty seven four-year-old Romney ewes were offered a medium (1164 ± 31.6 and 819 ± 16.0 kg DM/ha pre- and post-grazing pasture mass, respectively) or ad libitum (2181 ± 47.6 and 1431 ± 24.6 kg DM/ha pre- and post-grazing pasture mass, respectively) feeding treatment from day 76 of pregnancy until after lambing. At ear-tagging the time taken for the lambs to stand, make contact with, suck from and follow their dam was recorded. A maternal behaviour score based on the distance the ewe moved away from her lambs during tagging was also recorded. Survival analysis showed that lambs born to ewes offered the medium feeding treatment from mid pregnancy until lambing were quicker to stand, suck and follow compared with lambs born to ewes offered the ad libitum feeding treatment (P<0.05). It is unclear whether these behaviours indicate that lambs born to ewes in the medium treatment were more vigorous or that they had unmet needs that prompted the apparent increase in vigour. Ewe feeding treatments did not affect the maternal behaviour of the ewes.

Does mowing before grazing increase dry matter intake and milk yield? - Bryant RH; Kingsbury LA; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2016)
Mowing pasture before allocation of herbage to dairy cows is one management strategy suggested to improve feed quality, increase herbage dry matter (DM) intake and increase milk solids yield. To test these hypotheses, pasture at either a three or four week regrowth interval was offered to dairy cows 3 hours after pasture had been mown or as standing pasture. Forty-eight late lactation, Friesian x Jersey dairy cows were blocked into four groups and randomly allocated to each treatment. There was no effect of mowing or regrowth interval on botanical composition of the pasture on offer. Composition of herbage above 3.5 cm varied in DM content which was increased by mowing (13.2 versus 18.4% DM, P<0.05). For pastures with a three week regrowth interval, crude protein content was higher in the mown compared with standing herbage. At a similar herbage allocation, apparent DM intake was lower in mown (14.9 kg DM/cow/day) than in standing (15.5 kg DM/cow/day) treatments (P<0.05). This resulted in lower milk solids yield (P<0.05) in mown (1.24 MS/cow/day) compared with standing pasture (1.40 kg MS/cow/day). There was no apparent advantage in mowing ryegrass pastures in late lactation to improve herbage utilisation, DM intake or milk yield.

Effect of grazing system on nitrogen partitioning in lactating dairy cows grazing irrigated pastures in Canterbury, New Zealand - Clement AR; Dalley DE; Chapman DF; Edwards GR; Bryant RH (Proceedings of the New Zealand Society of Animal Production, 2016)
Regulations currently being developed by Regional Councils throughout New Zealand to manage freshwater quality may require substantial reductions in nitrate leaching from dairy farms in many regions. The objective of this study was to quantify nitrogen intake, partitioning, and excretion in two irrigated farming systems in Canterbury, comparing different possible pathways for future industry development. A ‘higher input’ system (HI, n = 34 cows) was characterised by a stocking rate of 5 cows per/ha, ~300 kg/ha/year fertiliser N and ~1t DM/cow/year purchased supplement fed on the milking platform. The ‘lower input’ system (LI, n = 29 cows) used a stocking rate of 3.5 cows/ha, 150 kg/ha/year fertiliser N, and minimal purchased supplement. Urine, faeces, plasma, and milk samples were collected for N determination at consecutive afternoon and morning milkings once per month for four years. Estimated N intake did not differ between HI and LI (537 g N/cow/day and 557 g N/cow/day respectively, P = 0.29). No differences were recorded for N parameters and estimated milk and urine N output/cow was not affected by farm system. When scaled to per hectare, urinary N excretion was 33% greater for HI compared with LI (1.1 kg/ha/day and 0.8 kg/ha/day, respectively, P = 0.02).

Estimation of genetic parameters for milk yield traits at different herd production levels in cows milked once- or twice-daily in New Zealand - Lembeye F; Lopez-Villalobos N; Burke JL; Davis SR (Proceedings of the New Zealand Society of Animal Production, 2016)
The objective of this study was to estimate genetic parameters for lactation yields of milk (MY), fat (FY) and protein (PY) for cows milked either once- (OAD) or twice-a-day (TAD) at different production levels (PL), calculated as average milk solids yield (FY + PY) for dairy cattle in New Zealand. Lactation records of 124,620 and 194,631 cows from 298 and 350 herds milked OAD and TAD, respectively were used. Heritiabilities (h2) were lower in low PL herds milked OAD compared to low PL herds milked TAD (0.11-0.18 vs. 0.22-0.37). Across PL, h2 for MY at medium and high PL were greater than 0.30 at both MF, while for FY and PY, those values were less than 0.30. Genetic correlations (rG) between MY and PY were greater (>0.70) compared to rG between FY and any of the other traits (<0.65). The lowest rG was observed between MY and FY at low PL (0.09±0.087). In conclusion, lower h2 at low PL from cows milked OAD reveal unequal genetic expression of milk traits genes compared to higher PL. Ignoring the heterogeneity of variance in the genetic evaluation could result in systematic inaccuracies and biases in the estimation of breeding values for cows milked OAD.

Genetics of alternative definitions of feed efficiency in grazing lactating dairy cows - Hurley AM; Lopez-Villalobos N; McParland S; Lewis E; Kennedy E; O'Donovan M; Burke JL; Berry DP (Proceedings of the New Zealand Society of Animal Production, 2016)
There has been anecdotal evidence of increasing liver abscessation on bull-beef farms across New Zealand from meat processors for more than a decade, but to date, no quantitative data has been published in the field. This study objective was to establish the incidence of liver abscessation in pasture- based beef bulls, the seasonality and breed differences, the impact on carcass weight, and to compare this with published data from feedlot cattle internationally. The study used a database of 137675 bulls slaughtered in the South Island between 2000-2005. The database included breed, farm location, carcass weight, liver abscess presence and abscess grading score (absent, mild, moderate, severe). The annual incidence of liver abscessation calculated was a mean of 9.5%. This recorded value is greater than other observed incidences from pasture-based systems and reduced compared with those observed in non-medicated feedlot systems internationally. There were significant variations in all measured parameters across years, and a clear and significant seasonal variation was observed. Incidence of liver abscessation peaked across November- December (11.3 and 11% respectively) and then declined as the slaughter season progressed. The typical NZ beef industry approach to rearing bulls for slaughter makes it likely that age at slaughter is a key influence on the seasonal incidence rate, with most cattle born in spring and slaughtered after 18 months, suggesting the late spring and summer peak in incidence is due to bulls older than two years. The percentages of abscesses graded were: severe (66.4%), moderate (12.8%), and mild (20.7%). Friesian and dairy crossbreed bulls had an incidence approximately twofold greater than that females beef breeds (10.3% and 4.7% respectively). There was a significant difference in the mean carcass weights of bulls graded, with those moderate with abscessation having a mean heavier carcass weight than those graded severe, minor and no abscess.

Grazing behaviour and species selection of heifer calves fed different forages. - Back PJ; Hickson RE; Lilly VM; Coleman LW; Sneddon NW; Laven RA (Proceedings of the New Zealand Society of Animal Production, 2016)
The aim of this experiment was to determine whether there was a difference in the behaviour of calves grazing different forages. Weaned dairy heifer calves (n = 64) were assigned to two different forage feeding treatments: ryegrass pasture and a clover-herb mix. Behavioural observations were recorded every 10 minutes over a 72 h period. Behaviours recorded were standing, walking, lying or sitting, grazing, ruminating, drinking/grooming, playing and various combinations of these. Calves grazing pasture spent more time lying and ruminating compared to calves grazing the clover-herb mix (34.6% vs 16.7%), and less time standing and grazing (17.2% vs 32.2%). Calves were less active from late evening and early morning and more likely to be ruminating earlier in the day and grazing later in the day. Plant selection (measured as plant disappearance rate) was determined in calves grazing the clover-herb mix. Red clover had the highest disappearance rate on all days compared to other species (P<0.05). Plantain, chicory and white clover eaten on day one did not differ in proportions eaten, but by day three less red clover and chicory remained compared to plantain and white clover (P<0.05).

Growth of early weaned lambs on a plantain-clover mix compared with lambs suckling their dam on a plantain-clover mix or a grass based sward - Cranston LM; Corner-Thomas RA; Kenyon PR; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2016)
Plantain-clover mixes have high metabolisable energy content and have been shown to support greater liveweight gains in lambs both pre- and post-weaning when compared with grass. The aim of this experiment was to determine if a plantain-clover mix could be used as a means to wean lambs earlier. Twin-bearing ewes (n=67) with both lambs at a minimum live weight of 16 kg each were allocated to one of three treatments; 1) ewe and lambs together on grass, 2) ewes and lambs together on plantain- clover mix, 3) lambs weaned at approximately 8 weeks of age onto a plantain-clover mix and ewes on grass. Lambs that were weaned early were lighter (P<0.05) at approximately 14 weeks of age than those which remained with their dam on either a plantain-clover mix or grass (32.3±0.43 vs 34.7±0.44 vs 33.7±0.45 kg, respectively). However, ewes which had their lambs weaned early were heavier (P<0.05; 79.7±1.73 vs 75.5±1.68 vs 75.9±1.64 kg, respectively) and in better body condition score (P<0.05; 3.1±0.05 vs 2.9±0.05 vs 2.9±0.05, respectively) than those which remained with their lambs on either a plantain-clover mix or grass. This suggests early weaning improved ewe condition but did not improve lamb performance

The impact of lamb growth rate pre- and post-weaning on farm profitability in three geoclimatic regions - Thompson BR; Stevens DR; Scobie DR; O'Connell D (Proceedings of the New Zealand Society of Animal Production, 2016)
Sheep and beef farmers target an increase in lamb growth rates as a means of increasing on-farm profit. Increasing any performance parameter invariably increases feed demand, resulting in either a need to increase feed supply or reduce feed demand in some other area of the farm system, therefore potentially affecting profit. A whole-farm-system model was used to assess the impact of increasing lamb weaning weight and post-weaning growth rate on farm profit and enterprise selection of three farms from three regions (Otago, Gisborne and Northland). Farm profit did not always increase with an increase in weaning weight or post-weaning growth rate. Farm profit was highest in the cool temperate region when weaning weight was at the base weight (27 kg) and post-weaning growth rate was 75 g/d greater than current. Farm profit was highest in the dry temperate region when weaning weight was 32 kg (6 kg above the base weight) and post-weaning growth rate was 50 g/d greater than the base growth profile. In the warm, temperate region, farm profit was highest at the two extremes, the highest weaning weight (30.6 kg) and post-weaning growth rate profile (100 g/d greater than the base profile) and at the lowest weaning weight (24.6 kg) and post-weaning growth rate profile (50 g/d less than the base profile). This demonstrates the interactions and trade-offs between feed supply and lamb growth rate on farm, and highlights that increasing lamb liveweight gain does not necessarily equate to increased profit.

The incidence of liver abscessation in slaughtered beef bulls in the South Island of New Zealand - Trotter CG; Gibbs SJ (Proceedings of the New Zealand Society of Animal Production, 2016)
There has been anecdotal evidence of increasing liver abscessation on bull-beef farms across New Zealand from meat processors for more than a decade, but to date, no quantitative data has been published in the field. This study objective was to establish the incidence of liver abscessation in pasture- based beef bulls, the seasonality and breed differences, the impact on carcass weight, and to compare this with published data from feedlot cattle internationally. The study used a database of 137675 bulls slaughtered in the South Island between 2000-2005. The database included breed, farm location, carcass weight, liver abscess presence and abscess grading score (absent, mild, moderate, severe). The annual incidence of liver abscessation calculated was a mean of 9.5%. This recorded value is greater than other observed incidences from pasture-based systems and reduced compared with those observed in non-medicated feedlot systems internationally. There were significant variations in all measured parameters across years, and a clear and significant seasonal variation was observed. Incidence of liver abscessation peaked across November- December (11.3 and 11% respectively) and then declined as the slaughter season progressed. The typical NZ beef industry approach to rearing bulls for slaughter makes it likely that age at slaughter is a key influence on the seasonal incidence rate, with most cattle born in spring and slaughtered after 18 months, suggesting the late spring and summer peak in incidence is due to bulls older than two years. The percentages of abscesses graded were: severe (66.4%), moderate (12.8%), and mild (20.7%). Friesian and dairy crossbreed bulls had an incidence approximately twofold greater than that females beef breeds (10.3% and 4.7% respectively). There was a significant difference in the mean carcass weights of bulls graded, with those moderate with abscessation having a mean heavier carcass weight than those graded severe, minor and no abscess.

The influence of age and breed of cow on colostrum indicators of suckled beef calves - Hickson RE; Back PJ; Martin NP; Kenyon PR; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2016)
Rearing a calf to weaning is a key measure of performance in a beef breeding cow herd. Adequate intake of colostral antibodies by the calf in the first few hours of life is important for passive transfer of immunity, and so is beneficial for calf survival. This experiment aimed to examine the role of udder conformation, maternal age and breed-cross on the colostral status of suckled calves. Udder conformation of Angus, Angus-cross-Friesian, Angus-cross-Jersey and Angus-cross-Kiwicross cows was scored according to Animal Evaluation Limited and BreedPlan standards, and colostral status of calves was determined based on gamma glutamyltransferase activity, immunoglobulin G and total protein concentrations at 24-48 hours of age. Udder conformation was similar (P>0.05) among breed-crosses except Angus cows had looser front udder attachment, lower rear udder attachment and less desirable udders overall than Angus-cross-dairy cows (P<0.05). Most udder conformation scores did not affect colostral status of calves. The exception was teat placement score, for which more outward-pointing teats were associated with improved colostrum status of calves (P<0.05). Survival to weaning was greater for calves with adequate compared with inadequate colostral status (P<0.001).

The influence of previous reproduction on subsequent fertility in multiparous ewes - Scobie DR; O'Connell D; Noble A; Greer AW (Proceedings of the New Zealand Society of Animal Production, 2016)
Adult ewes often lose live weight while lactating, but should regain it prior to the following mating if pasture availability or sheep numbers are managed judiciously. Data from a self-replacing flock of Wiltshire ewes four to nine years of age (n=267) was available for 622 lambing events across a 13-year period. Wiltshires grow little wool and live weight was not complicated by fleece weight. The average number of lambs born was 1.76 per ewe per year during the course of the study. Ewes not rearing a lamb (13.2%), or rearing singles (42.4%), twins (42.4%), or triplets (1.9%), were present at weaning. All ewes were grazed together and when their lambs were weaned, those that did not raise a lamb (67.4 ± 9.7 kg) were heavier than ewes that raised singles (63.0 ± 9.3 kg), twins (59.9 ± 8.5 kg) or triplets (59.7 ± 7.7 kg) (P<0.001). Despite this, the previous number of lambs weaned did not influence the number of lambs born in the subsequent year (P = 0.43), but was positively associated with ewe liveweight gain between weaning and mating (P<0.01). Number of lambs born was positively influenced by ewe live weight at mating up to 65 kg. Reproductive performance was not influenced by the previous year, providing ewes were able to increase live weight between weaning and mating.

Milk production and urinary nitrogen excretion of dairy cows grazing perennial ryegrass-white clover and pure plantain pastures - Box LA; Edwards GR; Bryant RH (Proceedings of the New Zealand Society of Animal Production, 2016)
Milk production and urinary nitrogen (N) concentration were measured in late lactation dairy cows grazing a perennial ryegrass- white clover pasture, pure plantain and an area that is comprised of 50% perennial ryegrass-white clover and 50% pure plantain by ground area (50-50 pasture-plantain), (n=12). Milksolids production was greater (P=0.01) for cows grazing plantain (1.67 kg MS/cow/d) than those grazing pasture (1.50 kg MS/cow/d), with cows grazing 50-50 pasture-plantain intermediate (1.60 kg MS/cow/d). Urine-N concentration was 56% lower (P<0.001) for plantain (2.4 g N/L) and 33% lower for 50-50 pasture-plantain (3.6 g N/L) than pasture (5.4 g N/L). Plantain may offer environmental benefits to dairy systems by reducing the urinary N concentration deposited on the soil from grazing cows in late lactation.

More dairy heifers are achieving liveweight targets - Handcock RC; Lopdell TJ; McNaughton LR (Proceedings of the New Zealand Society of Animal Production, 2016)
Dairy heifers should reach industry liveweight targets that are set to ensure heifers achieve good reproductive performance and milk production. The aim of this study was to determine if more dairy heifers born between the 2011-12 and 2014-15 dairy seasons (current) in New Zealand are achieving liveweight targets since a study on heifers born between the 2006-07 and 2010-11 dairy seasons (historic). In all age groups the mean live weight of current heifers was heavier than that of historic heifers. There were also a greater percentage of the current heifers at or above their target live weight compared with the historic heifers (P<0.001), suggesting that the rearing of dairy heifers has improved. The greatest improvement was seen at 15 months of age (mating) when 25% of historic heifers were at or above target compared with 56% of current heifers. Despite the improvement, 44% of current heifers were below target at mating and 65% were below target pre-calving (22 months of age). At 22 months of age, current heifers were on average nearly 42 kg below target live weight. By failing to achieve targets near calving, farmers are not capturing potential milk production benefits.

Performance and intake of high-yielding Holstein cows offered a TMR either alone or with access to grazing for six hours per day - Atkins NE; Cianchi C; Rutter SM; Williams SJ; Gauld C; Charlton GL; Sinclair LA (Proceedings of the New Zealand Society of Animal Production, 2016)
Grazing of lactating cows is a decreasing practice in Europe despite numerous potential benefits. In parts of Europe, farmers are required to graze all dairy cows for at least six hours per day during summer, but little is known about the effect on the performance of high-yielding animals. A study was undertaken to investigate the effects of the following treatments on high-yielding Holstein cow performance: continuous housing (C; control) with a total mixed ration (TMR), a six-hour grazing period directly after morning milking with TMR offered ad libitum when housed (EG; early grazing), a six-hour grazing period following morning milking with 75% of ad-libitum TMR when housed (RT; restricted TMR), or TMR access for one hour following morning milking, followed by a six-hour grazing period (DG; delayed grazing) then housed with TMR offered ad libitum. Total dry matter intake (DMI) was similar in C, EG and DG but lower in RT (26.9, 26.0, 26.7 and 23.8 kg DM/cow/d; P <0.001; SED 0.524). Milk yield was also lowest in RT, with mean values of 45.7, 44.2, 44.9 and 41.7 kg/cow/d in C, EG, DG and RT respectively (P =0.001; SED 0.993). High-yielding cows can be grazed for a six-hour period during the day with little impact on milk production provided TMR is unrestricted when housed.

Performance recording of NZ Corriedales - Booker J (Proceedings of the New Zealand Society of Animal Production, 2016)
Personal photo archives (W.R.E Booker) dated from 1926, showed early Corriedale ewe lambs were phenotypically similar to a cross between Ryeland and Southdown sheep. Since then both phenotypic and productive traits have been dramatically improved. This paper will review the history of the breed improvement in NZ Corriedales from the perspective of a sheep breeder. Prior to 1970 very little performance recording took place in the Corriedale breed. There was however a huge importance placed on phenotype with show ribbons and certificates being highly sought after not only for prestige among the breeder society but as they usually led to sales of rams to commercial breeders.

Preliminary investigations into the trait of residual energy intake in sheep - PL Johnson; Miller SP; Knowler K (Proceedings of the New Zealand Society of Animal Production, 2016)
Residual energy intake (REI), also referred to as residual feed intake, is one way of describing feed efficiency, and is an estimate of whether or not an animal is eating more or less than expected for its weight and growth rate. The REI trait has been investigated in a number of production-animal species, but only pilot study data exists for New Zealand sheep. This paper investigates phenotypic variability in the trait of REI for a cohort of 197 growing ewe lambs. The animals were approximately nine months old at the commencement of the trial. Their daily intake of a lucerne pellet-diet was measured for 56 days using an automated feeder that recorded weight of feed consumed in real time. The animals were weighed twice weekly. The standard REI model involves fitting metabolic mid-test live weight and live weight gain to predict energy intake. Both measurements fitted were significant (P<0.001), with an overall R2 for the model of 0.78. Grouping of the animals in to Low-, Mid- and High-efficiency groups revealed a 24% difference in energy intake between the low and high groups which is consistent with studies in other species. The comparison of attributes of the efficiency groups did reveal differences in fatness with the high-efficiency animals fatter at the start of the data collection, but they did not lay down as much fat during the trial as the low-efficiency group. Given the phenotypic variability is consistent with that observed in other production-animal species, additional cohorts will be measured in the coming years to generate a data set to investigate the genetics of the trait, and further investigate the role of fat within the REI model.

Relationship between social dominance and milk production of dairy cows grazing pasture - Hussein AN; Al-marashdeh O; Bryant RH; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2016)
The objectives of this experiment were to study factors determining social dominance of grazing dairy cows and the relationship between social dominance and milk production under grazing systems. A total of 252 spring calving Friesian x Jersey dairy cows in three groups differing in stocking rate and herd size grazing perennial ryegrass and white clover pasture were observed for three months in early lactation to determine their dominance value. All cows ranged in age from 2 to 11 years and live weight (LW) ranged from 340 kg to 648 kg. Dominance values were determined by social interactions indicating dominance and submission between cows. Social interactions were recorded on a win and loss basis. In all three groups, the dominance value was positively correlated (P<0.05) with age (r = 0.42 to 0.65), live weight (r = 0.33 to 0.47) and milk production (r = 0.32 to 0.42), but no relationship with body condition score was found. In conclusion, older cows with higher live weight were more dominant and tended to have higher milk production.

Reproductive performance of singleton and twin female offspring born to ewe-lamb dams and mature adult dams - Loureiro MFP; Pain SJ; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2016)
This study was undertaken to compare the reproductive and live weight performance of female singleton and twin ewes born to either mature or young dams from 18 months to 2.5 years of age. One hundred and fifteen singleton- and twin-born female offspring born to either ewe-lamb (8 months at breeding) or adult ewe dams were maintained as one cohort under commercial New Zealand grazing conditions. Ewe live weights and body condition scores were recorded, as were ovulation rates at a synchronised breeding and number of fetuses present at pregnancy scanning. The live weight of ewes born to ewe-lambs were lighter (P<0.05) than those born to adult ewes at breeding and during their first pregnancy but not (P>0.05) at the weaning of their lambs. Twin-born ewes were lighter (P<0.05) than their singleton-born counterparts. There was no difference in corpora lutea number (P>0.05) at breeding or number of fetuses at pregnancy scanning. Lambs whose grand dam was a ewe-lamb were heavier at birth (P<0.05) but not at weaning (P>0.05) compared to those lambs whose grand dams was an adult ewe. This data suggests there are few negative impacts from selecting progeny born to ewe lambs as replacement ewes. However, before this hypothesis can be supported, lifetime data of these ewes needs to be collected.

Reproductive production constraints within the New Zealand racing industry - Rogers CW; Gee EK; Bolwell CF (Proceedings of the New Zealand Society of Animal Production, 2016)
The New Zealand Thoroughbred industry has seen rationalisation in response to changes in the domestic market and more recently the Global Financial Crisis (GFC). To quantify changes in production, end-of-season reproductive data for active Thoroughbred sires were extracted for the 1989/90 to 2011/12 breeding seasons. There were reductions in the numbers of mares bred and foals produced (10,176 mares & 5,882 foals vs. 5,826 mares & 3,927 foals, respectively in 1989/90 and 2011/12 seasons) resulting in a greater relative proportion of foals registrations (57% vs. 67%). During this period, the number of active sires decreased (265 vs. 94) and number of mares per sire increased (33 IQR 18-53 vs. 49 29-91). The 2007/08 season (GFC) was associated with an acute reduction in the number of shuttle stallions imported for breeding (from 23% in 2006/07 to 11% of active sires in 2007/08), and a temporary increase in number of mares bred (13%), in response to the 2007 Equine Influenza outbreak in Australia. The proportion of sires covering >100 mares per season increased from 6% (1989/90) to 25% (2011/12). Despite the reduction in active broodmares during the same period (43%), there has not been a proportional decrease in export numbers (24%) or domestic numbers of horses racing (6.5%).

Supply curves for yields of dairy products from first-lactation Holstein Friesian, Jersey and Holstein Friesian-Jersey crossbred cows accounting for seasonality of milk composition and production. - Sneddon NW; Lopez-Villalobos N; Davis SR; Hickson RE; Shalloo L; Garrick DJ (Proceedings of the New Zealand Society of Animal Production, 2016)
The economic efficiency of a milk-processing system is influenced by seasonality of the milk supply, and changes to milk composition, influences the product potential of that milk. Lactation curves for milk yield and composition for seasonal calving first-lactation Holstein Friesian (F), Jersey (J) and Holstein Friesian-Jersey crossbred (FxJ) cows were used as inputs in a deterministic simulation model to produce seasonal curves for daily yields of dairy products. The dairy products were whole milk powder, skim milk powder, cheese, or butter. Dairy product potential was estimated for each animal from a population of 4333 mixed-breed, first-lactation cows. Lactation lengths differed (P<0.0001), among F, FxJ, and J, which averaged 219, 222 and 221 days respectively. Total-lactation milk yield was different (P<0.0001) among breeds and averaged 3257, 3092 and 2902 litres for F, FxJ and J cows, respectively. Whole-milk powder potential (yield per 1000 L of milk) was greatest at the start of the season and least at the end of the season, whereas cheese-production potential (yield per 1000 L of milk) followed the opposite pattern. Total-lactation whole-milk powder yield was different among breeds (P<0.0001) at 366, 338 and 312 kg of whole-milk powder for F, FxJ and J cows, respectively. Total-lactation cheese yield was also different among breeds (P<0.0001), and was 371, 375 and 361 kg for F, FxJ and J cows, respectively. The supply curves indicate that milk is best processed into whole or skim milk powder during peak season, and cheese and butter at the end of lactation. However, seasonal production of specific products would limit the use of by-product lactose from cheese manufacture in the production of milk powders, and thus negate the efficiency gains from changes to processing priorities.

Sustained diuretic effect of plantain when ingested by sheep - O'Connell CA; Judson HG; Barrell GK (Proceedings of the New Zealand Society of Animal Production, 2016)
Narrow-leaved plantain (Plantago lanceolata L.) was investigated for its potential to act as a diuretic in sheep. For seven days, two groups of sheep (n = 8) were provided with either ryegrass or plantain diets that had similar water content. Dry matter in feed, fresh faecal weight, and faecal water content was measured daily, as well as volume, specific gravity and osmolality of urine. Urine volumes on Day 1 of the trial were significantly different to those of Days 2-6 of the trial (P < 0.05) so the results were analysed separately. Plantain sheep had a higher volume of urine (by 1.7 L, P < 0.05) on Day 1 than Ryegrass sheep and continued to produce about 0.5 L more urine each day than Ryegrass sheep for the remainder of the study period. Because intakes of feed and feed water content for the two diets were essentially equal, this study provides the first direct evidence to show that plantain causes a diuresis when it is ingested by sheep, possibly by reducing reabsorption of water in the kidneys.

Urine volume of non-lactating dairy cows in late gestation fed forage based diets in winter - Farrell LJ; Bryant RH; Hague H; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2016)
Quantitative information on urine volume of dairy cows fed winter forages is required to accurately evaluate nitrate leaching risks on these diets. Thirty-two Friesian x Jersey non-lactating, pregnant dairy cows were fed either 10 kg DM of fodder beet with 5.6 kg DM of ryegrass baleage or 16.4 kg DM of kale with 6.4 kg of oat silage. Cows were fitted with a urine meter for 24 to 72 hours to record the frequency and volume of urine events. Daily urine volume (28 ± 3 L/cow/day), frequency (9 ± 0.89 events/cow/day), and event volume (3.2 ± 0.3 L/event) were not significantly different between fodder beet and kale treatments. This was despite respective differences in total apparent water (51 vs. 70 L/cow/day, ± 2, P<0.001) and nitrogen (N) intake (231 vs. 488 g N/cow/ day, ± 9.4, P<0.001). In this study, water consumption and N intake did not appear to be linked with urine volume of dairy cows when two different forage diets were compared.

Using genomic information to predict sex in dairy cattle - Zhang IL; Couldrey C; Sherlock RG (Proceedings of the New Zealand Society of Animal Production, 2016)
Sex misassignment of animals in breeding programmes can arise from sources such as misidentification and data-entry errors. The objective of this study was to develop a test for checking sex using Single Nucleotide Polymorphism (SNP) chip genotypes on chromosome X. All animals in this study were genotyped using the GeneSeek Genomic Profiler LD v3 (GGPv3) SNP chip. After filtering, 16478 sex-verified animals (15703 cows and 775 bulls) were available in the training set. The proportion of heterozygous SNPs on chromosome X was used to predict sex. The distribution of heterozygosity was bimodal in the training population with a clear gap between 0.01 and 0.03. Using the heterozygosity cutoff of 0.02 resulted in 100% and 99.6% prediction accuracy for males and females, respectively. Additional analysis determined that four incorrectly classified females were either XO or inbred. The test was validated on an independent set of 2212 animals, which resulted in seven animals for which the predicted sex differed to the recorded sex. Physical examination of these animals revealed that the predicted sex was correct in all cases. The method developed is a useful addition to quality control of genotypes obtained as part of a genomic selection programme.

Variation in total body adipose and adipose partitioning in maternal sheep estimated using computed tomography scanning - PL Johnson; Bain WE; Johnstone P; Bixley M; Knowler K (Proceedings of the New Zealand Society of Animal Production, 2016)
In sheep, decreasing adipose or fat is desirable in prime lambs; however, adipose also has a role in the productive capacity of the maternal ewe. There are three main depots of adipose within the body of a live animal: sub-cutaneous, intermuscular and internal (or visceral). To understand if differences exist between animals in adipose deposition and partitioning, a study was undertaken using 37 New Zealand composite-breed maternal ewes, scanned using computed tomography on three occasions from nine through to 17 months of age. The images produced were processed to estimate the weight of subcutaneous, intermuscular and visceral adipose (along with lean and bone), with the weights then expressed as a percentage of total adipose to investigate partitioning. The raw average total body adipose remained proportionate across the three scans at approximately 32% of total empty body weight. The resulting data were analysed using a REML variance components analysis in Genstat. The repeatability of fat distribution across the three scans was high, ranging from 0.77 for proportion of intermuscular adipose through to 0.83 for proportion of subcutaneous adipose. The component Animal was significant for all traits indicating between animal variation in partitioning of adipose between the depots within individual animals. Cumulatively, these results demonstrate that there is variability in adipose deposition and partitioning in New Zealand sheep. If under genetic control, variability that could be exploited to optimise adipose to best meet the requirements of prime lamb production and maternal ewes.

2015 NZSAP Living Legend Address – Invermay Agricultural Centre - Shackell GH; Drew KR; Fennessy PF; Allison AJ; McEwan JC; Crawford AM (Proceedings of the New Zealand Society of Animal Production, 2015)
Some of the best science is done by those who are excited by their research and by working with industry. Many breakthroughs come from people noticing, and following up on, unusual observations or anomalies. Often, their passions are funded “from the back pocket” for several years; until sufficient information is secured to justify a formal funding application. The Living Legend Lecture invites distinguished longterm members of NZSAP to make a scholarly presentation at the Society’s annual conference in recognition of their contribution to New Zealand Animal Production over a substantial period of time. Heeding the Guidelines recommendation to consider members resident in the area holding the conference, the 2015 organising committee chose to nominate the contributions of the scientists and technical staff of an iconic Institution, rather than acknowledge a single individual’s work. No specific animal production “theme” was selected. Instead, it was decided to highlight the contribution of the Invermay Agricultural Centre as a whole...

Abstracts from the Ewe milk products and sheep dairy conference 2015 - Anonymous (Proceedings of the New Zealand Society of Animal Production, 2015)

Analysing hidden patterns of farmers’ preferences for farm performance characteristics that may be related to tail-docking practice decisions - Martin-Collado D; Byrne TK; Amer PR; Behrent MJ; Maclennan G; Kerslake JI (Proceedings of the New Zealand Society of Animal Production, 2015)
We investigated how multivariate statistics can be used to determine the different patterns of preferences that may exist within a farmer population. As a case study, we used adaptive conjoint analysis to analyse farmers’ preferences for nine farm performance characteristics that may be related to tail docking practice decisions. As expected, at the whole population level, farmers’ preferences for these traits were found to be highly heterogeneous, with only the most important issues and least important issues being able to be statistically differentiated. Using Cluster Analysis and Principal Components Analysis we found some hidden relationships and identified the existence of four groups of farmers that had greater preferences for different characteristics; group one preferred having less dags and less costs associated with dagging and crutching, group two preferred to reduce euthanasia from uterine prolapse and rectal prolapse, group three preferred to avoid stressing lambs at the time of docking and group four preferred to have less fly-strike and greater weaning weights. We discuss how the use of multivariate statistics allowed a deeper interpretation of preference studies in a context of importance to NZ farmers.

Beef cattle wintering systems: effects on cattle and pasture. - Little CL; Hickson RE; Martin NP; Beausoleil NJ; Cockrem JF; Kenyon PR; Horne D; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2015)
The wet winter months are a risk period for damage to pasture under grazing systems in New Zealand. The use of stand-off pads and alternative forages and grazing systems may alleviate these risks, but may also impact on the performance and welfare of cattle. This experiment compared four wintering systems for growing beef calves (9–11 months old, n=103) in terms of growth rate and welfare of calves, and damage to pasture. Treatments were a forage crop of oats, set-stocked grazing on pasture, breakfed on pasture, and break-fed on pasture with use of a concrete feedpad and wood-shavings stand-off area when the soil was wet. Liveweight gain was greatest (P<0.05) for the set-stocked (0.81±0.02 kg/day) and break-fed calves (0.52±0.02 kg/day), and least for the calves in the feedpad (0.19±0.02 kg/day) and crop treatments (0.10±0.02 kg/day). The percentage of calves lying down was least in the break-fed and oats treatments (P<0.05) but faecal corticosterone concentration was greatest in the feedpad treatment (P<0.05). Pasture damage was greater under rotational grazing (score 3.8/5) than set stocking (score 2.9/5), but use of the feedpad did not prevent damage to pasture (score 3.4/5). Set-stocking had the best outcomes for calves and pasture.

Blank panels in sheep yards encourage sheep to jump - Scobie DR; O'Connell D; van Koten C; R Phiskie (Proceedings of the New Zealand Society of Animal Production, 2015)
The lateral sides of two adjacent forcing pens and the sides of the races were clad with plywood to improve sheep flow in yards at AgResearch Lincoln farm. Following this, two flocks of yearling sheep were run through the yards every two weeks for drafting. One flock was exclusively male (n = 223), while the other was all female (n = 248). On the first occasion, a number of yearlings jumped out of the forcing pen. This had not been observed in previous years, so the number jumping was recorded. A non-parametric time-to-event analysis method, the Kaplan-Meier estimator, was used to obtain cumulative incidence functions of sheep jumping. If they were to jump out of the pen, the sheep had two choices, a pipe rail fence (or gate) or a blank plywood wall. During 14 handling events, 1% of yearlings jumped the pipe rails whereas 7% jumped the plywood wall (P < 0.001). These yearlings chose to jump a fence they could not see through. Clearly there are many variables that could be tested in this model.

Body condition and morphometric measures of adiposity in a cohort of Pony Club horses and ponies in New Zealand - Fernandes KA; Rogers CW; Gee EK; Bolwell CF; Thomas DG (Proceedings of the New Zealand Society of Animal Production, 2015)
A cross-sectional study was conducted to describe and compare the body condition and morphometrics of Pony Club (PC) horses and ponies at two points in the year. Data were collected from a cohort of PC riders in spring (n=158) and autumn (n=155), with 73 repeat measurements across the two seasons. There were more ponies (68%, 164/240, wither-height ≤148 cm) than horses in the study population. Most (76%, 183/240) animals were kept on ad libitum pasture throughout the year and were fed small quantities of supplementary feed. The median body condition score (BCS) of the animals was 6 (interquartile range 5-7). Forty-seven per cent (112/240) of the animals were scored ‘fat’ (BCS ≥7) and 25% (61/240) presented with a cresty-neck score ≥3. There was poor inter-rater agreement between the study personnel and owners for BCS of horses (Kappa=0.26) and ponies (Kappa=0.11). The study personnel identified 54% (88/162) of ponies as ‘fat’, whereas owners underestimated the BCS of ponies, and identified only 40% (65/162) as ‘fat’ (P<0.001). The measurements of body weight did not differ between seasons, and only some morphologybased assessments of adiposity differed between seasons. Overall, 17% (15/88) of ‘fat’ ponies and 21% (11/53) of those with ‘cresty-necks’ were reported to have had a previous history of laminitis. Laminar rings were observed in 98% (234/240) of the PC horses and ponies. The study highlighted that horses and ponies kept on pasture maintain body weight and condition from spring to autumn, but this finding may be biased by the high percentage of ‘fat’ ponies in the study population. The poor inter-rater agreement for BCS, particularly with ponies, and similar morphological measurements between seasons, highlights the challenges with using these measurements of adiposity in ponies

BRIEF COMMUNICATION: Birth weight of calves born to dairy cows in New Zealand - Hickson RE; Zhang IL; McNaughton LR (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Chitosan is a highly effective in vitro antibacterial agent against the strains of bacteria causing footrot, but is not effective in treating stage-four footrot on farm. - Bekhit AEA; Mros S; Ali MA; McConnell M (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Composition of milk sampled from beef-cross-dairy cows unaccustomed to milking. - Hickson RE; Back PJ; Coleman LW; Lopez-Villalobos N; Kenyon PR; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Developing genomic tools in the New Zealand Deer Industry - Rowe SJ; Clarke SM; Van Stijn TC; Hyndman DL; Ward JF; McEwan KM; Dodds KG; McEwan JC; Newman S-AN; Asher GW (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Do high-milk diets affect the growth rate of heifers prior to weaning? - Cardoso DS; Hickson RE; Laven RA; Coleman LW; Back PJ (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Genetic control of the rumen microbiome in sheep - Rowe SJ; Kittelmann S; Pinares-Patiño CS; Wood GR; Dodds KG; Kirk MR; Ganesh S; Hickey SM; Janssen PH; McEwan JC (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Genetic parameters for growth, carcass and meat quality traits in New Zealand sheep - Brito LF; Miller SP; Clarke SM; Dodds KG; Bain WE; Lee MA; Pickering NK; McEwan JC (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Genetic parameters for meat traits assessed in the Headwaters New Zealand Progeny Test - PL Johnson; Charteris A; Tate ML; Dodds KG (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Intake of ewe lambs is influenced by the dry matter percentage of the feed consumed - PL Johnson; Miller SP; Knowler K; Bryson B; Dodds KG (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Metabolite profiling in New Zealand milk - Davis SR; Jaine J; Obolonkin V; Braggins TJ; Cooney TP; Scott A; Spelman RJ (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Modelling liveweight change to inform residual feed intake models in growing lambs - PL Johnson; Miller SP; Knowler K; Bryson B; Dodds KG (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Onset of breeding season in Dorset Horn ewes - PL Johnson (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Optimizing a fasting protocol to assess live weight of sheep - Wilson RF; Hardwick-Smith JA; Logan CM; Corner-Thomas RA; Bywater AC; Greer AW (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Substitution of perennial ryegrass with forage rape reduces methane emissions from sheep - Sun XZ; Sandoval E; Pacheco D (Proceedings of the New Zealand Society of Animal Production, 2015)

BRIEF COMMUNICATION: Walking distance and energy expenditure of beef cows grazing on hill country in winter - Martin NP; Hickson RE; Draganova I; Horne D; Kenyon PR; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2015)

Colostral immunoglobulin G as a predictor for serum immunoglobulin G concentration in dairy calves - Coleman LW; Hickson RE; Amoore J; Laven RA; Back PJ (Proceedings of the New Zealand Society of Animal Production, 2015)
Feeding newborn calves high-quality colostrum is of well-recognised importance as calves that do not receive an adequate concentration of immunoglobulin-G (IgG) have an increased risk of morbidity and mortality. This experiment aimed to characterise IgG concentrations in colostrum from the first milking in New Zealand dairy cows, examine IgG status of calves, and to evaluate the use of a refractometer for estimating quality of colostrum in terms of IgG concentration. Heifer calves entered the calf shed at 0-24 hours of age and were fed pooled first-milking colostrum within eight hours of entering the shed. Blood samples were taken the following morning. Cows were individually milked and samples from individual and pooled colostrum were analysed. IgG concentration of serum and colostrum samples were determined by turbidimetric immunoassay. IgG concentration was adequate according to commercial reference ranges in 70.1% of individual colostrum, 80.0% of pooled colostrum and 82.5% of calf serum samples. There was no relationship between calf serum and IgG concentration in dam or pooled colostrum. The refractometer was a good predictor of IgG concentration in serum (r=0.64, P<0.0001) and colostrum both in dam (r=0.87, P<0.0001) and pooled (r=0.81, P<0.0001) samples. The relationship between IgG concentration and refractometer reading indicates that it could be a useful on-farm tool.

A comparison of microbial protein synthesis in beef steers fed ad libitum winter ryegrass or fodder beet - Prendergast SL; Gibbs SJ (Proceedings of the New Zealand Society of Animal Production, 2015)
Microbial protein synthesis of steers (liveweight 286±9 kg) was compared with diets of ad libitum winter grass and fodder beet with 1 kg DM of lucerne silage. The experimental design was a four-by-two treatment comparison (experiment 1 and 2), using 11 day individual pen trials with total faecal and urinary collection. The trials assessed in vivo digestibility of diets, and diurnal variations in rumen parameters (pH volatile fatty acid, ammonia and urea concentrations) and urine and faeces production and N excretion. Microbial protein production was estimated from purine derivatives determined from total urine collection. Dry matter digestibility, voluntary dry matter intake and microbial protein supply to the steers, and the mean diurnal rumen pH, were higher in the steers fed the fodder-beet treatment than in those fed the winter-grass treatment. Fodder beet supplied almost twice as much microbial protein as winter grass despite a lower crude protein concentration of the diet. Total rumen VFA and ammonia concentrations were lower for the fodder-beet treatment than for winter grass but the rumen urea concentration was higher in the fodder-beet treatment. The observed high microbial protein supply with the fodder beet diets is likely the result of ruminal and extra-ruminal adaptations to greater nitrogen recycling in low dry matter diets of high energy density and low crude protein concentrations.

Contract session: Application of genetic technologies to the New Zealand sheep industry - Jopson NB; Linscott EM; Young MJ; Dodds KG; Clarke SM; Rowe SJ; Byrne TJ; Alder GF (Proceedings of the New Zealand Society of Animal Production, 2015)

The difficulties in reviewing ergovaline - Nicol AM; Klotz JL (Proceedings of the New Zealand Society of Animal Production, 2015)
The endophytic alkaloid, ergovaline, is a secondary metabolite of a number of endophytes associated with perennial ryegrass. Ergovaline is known to protect ryegrass against attack by a range of insect pests, but can also negatively affect domestic ruminants. We have recently reviewed the physiological responses and metabolism of ergovaline and the effect of its consumption on animal production. The main focus of this paper is on the difficulties encountered in preparing these reviews. These include the lack of a cost-effective source of ergovaline to allow for robust dose-dependent trials resulting in ergovaline treatments based on seed sources presented in a range of processed forms, or as ryegrass pasture in which ergovaline is often associated with other alkaloids. Intake of ergovaline is often difficult to predict because ergovaline concentration of the diet on offer may not represent the concentration in the diet consumed. Furthermore, the mean live weight and level of production of the experimental animals is not always available to allow a prediction of ergovaline intake. Any change in gut-fill in response to ergovaline consumption needs to be accounted for when assessing any impact on body weight. Experimental objectives need to be clear, as the effects of short-term ergovaline exposure can be masked in a production system by subsequent compensatory growth/production. By identifying these difficulties, we hope that future work on ergovaline may be more consistent and of greater value to further reviews.

Diurnal pattern of rumen environment and rumen fill in lactating grazing dairy cows - Saldias B; Gibbs SJ (Proceedings of the New Zealand Society of Animal Production, 2015)

The effect of dam age on ewe offspring productive performance and efficiency - Pain SJ; Loureiro MFP; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2015)
productive performance and efficiency of singleton ewe offspring to four years of age. Live weight was recorded every two months from birth to four years of age for singleton ewe progeny born to either ewe-lamb dams or adult ewes (ewe-lamb progeny: ELP, n = 20; adult-ewe progeny: AEP, n = 25). The number of lambs born and weaned, and weight (kg) of lamb born and weaned were determined for each ewe for each productive year and as a combined total. Ewe production efficiency was calculated for each year and as a combined total. Results show that AEP were heavier at birth and remained heavier until one year of age (P<0.05). Live weight was again greater (P<0.05) for AEP in mid-pregnancy in 2010 and at weaning in 2011. The number of lambs born and weaned and the weight of lamb born and weaned per ewe did not differ in any of the three productive years or for the combined total. Ewe production efficiency was not affected by dam age, with similar efficiencies reported for ELP and AEP. The results from this study show that despite experiencing a weight penalty, the productive performance and efficiency of singleton ewe progeny born to ewe-lamb dams, if conventionally bred themselves as 18 months of age, appears to be similar to that of singleton ewe progeny born to mature adult ewes.

Effect of dam age on the growth and body composition of singleton ram offspring to 11 months of age - Loureiro MFP; Pain SJ; Kenyon PR; Firth EC; Rogers CW; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2015)
Studies in sheep suggest that ewe-lamb dams produce smaller offspring compared to mature adult ewes. This study was designed to examine the growth trajectory, body composition and carcass characteristics of 48 singleton Romney male progeny born to either ewe-lambs (ELP; n = 17) or adult ewes (AEP; n = 21). Both dam groups were maintained together under commercial grazing conditions during breeding, pregnancy and lactation. After, weaning the ram lambs continued to be managed together under commercial conditions. Ram offspring were weighed and measured at birth. They were subsequently weighed every two months until 11 months of age (d322). At d322, nine ELP and 10 AEP were euthanised and several body-size and composition measurements were taken. The ELP were lighter and smaller (P<0.05) at birth compared with AEP and they remained significantly (P<0.05) lighter until d218. After d218 this difference in live weight became a tendency (P<0.1). Slaughter data revealed that ELP tended (P<0.1) to have more visceral fat than AEP (P<0.05). Similarly, dual-energy X-ray absorptiometry (DXA) was performed on the left hind-leg and showed that AEP tended to have greater (P<0.1) lean mass compared with ELP. Despite the liveweight differences and the tendency towards differences in adiposity observed at slaughter, ram lamb carcass weight and dressing-out percentage were unaffected indicating that ram offspring meat production from ewe-lamb dams is similar to that from mature adult ewes.

The effect of ewe nutrition and body condition score during very late pregnancy and the perinatal period on the behaviour of twin-bearing ewes and their lambs - Gronqvist GV; Hickson RE; Corner-Thomas RA; Kenyon PR; Stafford KJ; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2015)
Nutrition of ewes during pregnancy may affect the behaviour and survival of lambs. In this experiment, ewes were allocated ‘low’ (pasture mass 800-1000 kg DM/ha), ‘medium’ (pasture mass 1200-1400 kg DM/ha) or ‘high’ nutrition (pasture mass 1500-1700 kg DM/ha) from day 141 of pregnancy until weaning. All treatments included ewes of body condition score (BCS) 2.0, 2.5 or 3.0 as measured on day 98 of pregnancy to give a 3x3 factorial design. Behaviours of ewes and lambs were recorded in the paddock at tagging 3-18 hours after birth. Lambs born to ewes on the high treatment were quicker to stand than those on the low treatment (median time 15.5 versus 53.5 seconds; P<0.05), but neither group differed from lambs on the medium treatment (16.5 seconds; P>0.05). There were no differences among treatments or BCS groups in time taken for the lamb to make contact with dam, suck from dam or follow their dam. Maternal behaviour score of the ewes was not affected by BCS or treatment. The percentage of lambs that bleated was similar for lambs from all BCS groups and treatments. BCS and nutrition of ewes in late pregnancy and during the neonatal period had little influence on the behaviour of ewes and lambs.

The effect of grazing high-sugar ryegrass on lamb performance - Proctor LE; Craig HJB; McLean NJ; Fennessy PF; Kerslake JI; Behrent MJ; Chuah JCL; Campbell AW (Proceedings of the New Zealand Society of Animal Production, 2015)
A multi-year grazing study was undertaken on three commercial properties in the southern South Island to compare the performance of lambs grazing high-sugar ryegrass/white clover (HSG) with lambs grazing a standard ryegrass/white clover pasture (SRG). Cultivars were established in late spring 2012; approximately 400 lambs in each treatment group per property grazed the swards in autumn 2013 and summer/autumn 2014 at a density of 30 to 35 lambs per hectare. Lambs were weighed regularly throughout the season; those that reached the desired weight were sent for slaughter. Across both years and properties, lambs grazing the HSG pasture grew 31 grams per day faster (17%) on average than those grazing SRG (P<0.001). These lambs were an average of 0.4 kg heavier in terms of carcase weight at slaughter (P<0.001) yielding 0.2 kg more meat per carcase based on VIAScan yield. These results suggest that lambs grazing HSG outperform those grazing SRG.

Effect of shearing on lamb growth and carcase performance - McLean NJ; Craig HJB; Fennessy PF; Behrent MJ; Kerslake JI; Campbell AW (Proceedings of the New Zealand Society of Animal Production, 2015)
A study was undertaken on three properties throughout New Zealand to determine the impact of shearing on lamb performance and whether this offered any economic benefit to farmers as a farm-management tool. A total of 1,183 lambs were randomly allocated to one of four treatments, shorn fasted, bellied fasted, woolly fasted and woolly not fasted. Shorn fasted lambs grew 12 g/d faster than woolly fasted lambs (P<0.05), but at similar rates to bellied lambs and woolly not fasted lambs. There were no differences among treatments for carcase weight, meat yield or proportion of lambs killed at slaughter. The difference observed in average daily gain between the shorn fasted and the woolly fasted lambs, and the lack of difference observed between shorn fasted and woolly not fasted lambs, indicated that while shearing improved lamb growth rates, the weight loss due to fasting overnight was not overcome by the increased growth rate associated with shearing. While there was no economic benefit associated with lamb carcase weight or time to slaughter, at a wool price of $5.40 per kg clean, shorn lambs were still of a greater value to farmers compared to lambs from all other treatments.

The effects of feeding maize silage at different times prior to a herbage meal on dry matter intake, milksolids production and nitrogen excretion in late-lactation dairy cows - Al-marashdeh O; Greenwood SL; Hodge S; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2015)
The objective of this study was to determine the effect of feeding maize silage at different times before the herbage meal on dry matter (DM) intake, milksolids (MS) production and nitrogen (N) excretion of late lactation dairy cows. In an indoor study, nine Friesian × Jersey dairy cows were assigned to three treatments: (1) herbage only (control); (2) supplemented with 3 kg DM of maize silage after morning milking approximately nine hours before the herbage meal (9BH); and (3) supplemented with 3 kg DM of maize silage after afternoon milking approximately one hour before the herbage meal (1BH). Cows were offered ad libitum cut herbage (perennial ryegrass-white clover) for five hours from 1530 to 2030 h. Herbage DM intake was greater (P=0.03) for control than 1BH cows, but did not differ between control and 9BH or between 1BH and 9BH cows (13.71, 11.96 and 12.74 kg DM/cow/ day for control, 1BH and 9BH, respectively). The substitution of herbage by maize silage was greater (P=0.05) for 1BH than 9BH cows (0.56 vs 0.31 kg DM herbage per kg DM maize silage, respectively). Milksolids production did not differ between treatments (overall mean 1.33 kg MS/cow/day). Nitrogen concentration in faeces and estimated urinary-N excretion (g/day) were lower in supplemented than control cows. Under herbage restriction, it is important to consider time of maize silage supplementation relative to the herbage meal for managing substitution rate and urinary-N excretion.

Estimation of a premium for milk with a high concentration of unsaturated fatty acids based on farm and processor profit: A simulation study. - Silva-Villacorta D; Lopez-Villalobos N; Hickson RE; Blair H; MacGibbon A (Proceedings of the New Zealand Society of Animal Production, 2015)
The objective of this study was to determine, via simulation, the premium required for dairy farmers supplying milk with a high concentration of unsaturated fatty acids (UFA) to a dairy processor to equal the operating profit ($/ha) of average farms, under New Zealand conditions. Fifty average farms (AVE farms) and fifty farms that fed an oilseed supplement to dairy cows (UFA farms) were simulated. The processing of milk produced by AVE farms and UFA farms into skim-milk powder and butter was also simulated. The physical and financial characteristics of dairy farms and a dairy processor were investigated under two scenarios: 1) no premium for UFA and 2) a premium for UFA which equalled the operating profit ($/ha) of UFA farms to that of AVE farms. UFA farms were not different from AVE farms in yields of milk, milkfat and protein, but their farm expenses were greater (P<0.05) than for AVE farms. A premium of $0.15/kg milkfat (for each 0.1 g UFA/100 g milkfat increase) was necessary for UFA farms to have an operating profit ($/ha) similar to AVE farms. These results may be used to further evaluate the impact of modifying milkfat UFA concentration at the farm level.

Estimation of breed and heterosis effects for milk traits and somatic cell scores in cows milked once and twice daily in New Zealand - Lembeye F; Lopez-Villalobos N; Burke JL; Davis SR (Proceedings of the New Zealand Society of Animal Production, 2015)
Crossbreeding is widely used by famers milking twice-a-day (TAD) to increase farm profitability. Effects of crossbreeding on farm productivity and profitability have not been investigated in farms practicing once-a-day (OAD) milking. The aim of the study was to estimate breed and heterosis effects for lactation length (LL), total yields of milk (MY), fat (FY) and protein (PY) and average somatic cell score (SCS) in cows milked OAD or TAD. Records from 36,276 Friesian (F), 31,560 Jersey (J) and 90,081 crossbred (F×J) cows that calved in spring between 2008 and 2012 were used. Compared to J cows, F cows had a higher MY (657 kg in OAD and 1034 kg in TAD), FY (2.9 kg in OAD and 7.8 kg in TAD), PY (13.6 kg in OAD and 22.4 kg in TAD) and SCS (0.28 in OAD and 0.05 TAD). Lactation length in OAD cows was five days shorter than in TAD cows (P<0.05). These results show a significant interaction between breed and milking frequency for production traits (P<0.001). Expressed as a percentage of the average of parental breeds, first-cross heterosis effects ranged between 4.92 to 6.84% for production traits, and were similar across milking frequencies. The estimates of breed and heterosis obtained in this study can be used for simulation studies to evaluate the profitability of crossbreeding systems under OAD and TAD milking systems of typical New Zealand dairy farms.

Estimation of crossbreeding effects on yields of dairy products and value of milk processed in different product portfo - Sneddon NW; Lopez-Villalobos N; Hickson RE; Shalloo L; Garrick DJ (Proceedings of the New Zealand Society of Animal Production, 2015)
The international market requires milk products to meet specified minimum standards that define acceptable composition. This study used a deterministic simulation model to estimate milk products yields of individual cows for different export markets. Four milk product portfolios were analysed which included 100% of the milk to either whole-milk powder (WMP), skim-milk powder, cheese, or butter. Milk product potential was estimated for 4310 mixed-breed heifers from LIC Sire Proving Scheme herds based on total lactation production. Lactation lengths were 212, 214 and 213 days for Holstein Friesian (HF), Holstein Friesian-Jersey crossbreds (HFxJ), and Jerseys (J) respectively. Milk yields were significantly different between breeds averaging 3121 for HF, 2947 for HFxJ, and 2751 litres for J cows. Holstein Friesians had the lowest fat, protein and lactose concentrations, whereas J had the highest. Holstein Friesian had the greatest yields of WMP per 1000 litres of milk, whereas J had the least. For all scenarios, J milk was most valuable per litre. Crossbred cows provided greater total milk income for all scenarios except 100% butter. Positive heterosis effects were estimated for first-cross HFxJ animals for milk production and product yields. Crossbreeding produces cows with milk better suited to the processing requirements of the New Zealand dairy industry and returning greater value to the New Zealand dairy farmer.

Evaluation of production traits of red deer skins in the Deer Progeny Test. - Ward JF; Mathias-Davis HC; Cooper SM; Crawford EM; Wheeler M; Asher GW (Proceedings of the New Zealand Society of Animal Production, 2015)
Skins, hides and leather from deer are a valuable co-product of New Zealand venison production. Measurement of skin traits was included in the Deer Progeny Test to evaluate options for genetic selection, and to determine if selection for other production traits risks diminishing the quality of deer skins and leather. Skins of slaughtered eleven-month-old progeny (n=310) from terminal (wapiti crossbred) and maternal (red) sire types were evaluated for 18 different quantitative and qualitative traits throughout processing to pearl-crust leather. All processing was carried out by New Zealand Light Leathers. All traits were analysed using least squares means models with sire as the random term and pre-slaughter live weight as a covariate. For all traits except evenness grade of the pearl-crust leather, the relationship with pre-slaughter live weight covariate was significant (p<0.05) and positive. Sire had a significant effect (p<0.01) on eight traits including critical strength and finished-leather attributes (p<0.01), farm was also significant for eight traits (p<0.01). Average skin thickness was similar to published values. Sire can have an effect on important traits, and selection for higher slaughter weights of yearling red deer is predicted overall to increase the quality of skins and leather produced.

Flexural limb deformities in a cohort of Thoroughbred foals on commercial stud farms - Shotton AK; Bolwell CF; Rogers CW; Gee EK; Sells PD; Connell J; McIlwraith CW (Proceedings of the New Zealand Society of Animal Production, 2015)

From monitoring to precision phenotyping: towards a systemic use of precision livestock measures in dairy herds - Friggens NC; Thorup VM (Proceedings of the New Zealand Society of Animal Production, 2015)
There is an untapped potential to combine the measures from precision livestock farming to provide improved, biologically meaningful, phenotypes. At present, it is generally the case that precision livestock solutions are developed for the purposes of monitoring one particular condition, and very often using only one measure. It has been shown that combinations of precision livestock measures may provide a fuller, and more robust, description of the condition. These may be both combinations of full continuous signals (e.g., milk yield and electrical conductivity) or sequential combinations. Sequential combinations are those in which a cheap, easy-to-deploy but usually less precise signal is used to provide first-level monitoring but is set up to initiate a second-level, more precise, and usually more expensive, monitoring when the first indicator indicates change from the normal state. The usefulness of combined measures benefit from being developed with a systemic view of the underlying biology, leading to a subsequent improvement in the precision of the resulting phenotypes. The deployment of combined measures for phenotyping is becoming increasingly important, particularly in the context of addressing more complex traits such as robustness in genomic selection and when considering the animal’s role in herd level resilience.

Genetic parameters for meat yield and quality traits derived from the New Zealand Perendale progeny test - PL Johnson; Young EA; Russenklau D; Anderson T; Dodds KG (Proceedings of the New Zealand Society of Animal Production, 2015)
A catch phrase within animal genetics is that there is as much variation within a breed as there is between breeds. The New Zealand Perendale Progeny Test has been conducted on North and South Island sites since 2010 with the aim of investigating genetic variability for carcass traits. A total of 51 sires, from 27 studs have been assessed, with sires selected from the top 20% of the Perendale across-flock Dual Purpose Index SIL evaluation. Within each year/site lambs generated were born within a week (ewes naturally synchronised pre-mating), and slaughtered on the same day. A total of 2318 male progeny have been generated and slaughtered through Alliance with traits measured including weight traits, carcass dimensions, VIAscan® traits, carcass pH, carcass fat colour and, in some years, colour stability of chilled aged loins, subjective marbling score and meat tenderness. Genetic parameters were estimated with ASREML; carcass weight was fitted as a co-variate for carcass traits (excluding carcass weight). The heritability estimates for all traits were moderate to high, with the lowest of 0.22 ± 0.07 for VIAscan® GR, and the highest, for pH, of 0.44 ± 0.09, with the majority between 0.22 and 0.43. The high estimate for slaughter plant measured pH was supported by the 0.59 ± 0.17 estimate for pH measured in the laboratory on those samples which were measured for colour stability. The phenotypic correlations between traits were generally well estimated with small standard errors for the majority of trait combinations. The genetic correlations were not as well estimated with standard errors greater than 0.10 for most traits combinations, but despite the large standard errors some were still significant, and in general agreement with values the literature. The progeny test has therefore demonstrated significant genetic variability for the range of carcass traits assessed in this study within the Perendale breed.

Growth rate and carcass characteristics of Simmental- and Angus-sired steers born to Angus and Angus-cross-dairy cows - Collier KJD; Hickson RE; Schreurs NM; Martin NP; Kenyon PR; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2015)
Traditionally, British breeds have been the main source of beef produced in New Zealand. Recently the use of dairy breeds has increased. This experiment evaluates the growth rate and carcass characteristics of steers (n=64) born to straightbred Angus (AA), Angus-cross-Holstein Friesian (AF), Angus-cross-Jersey (AJ) or Angus-cross-Kiwicross (AK) dams, and sired by Angus (A) or Simmental (S) bulls. This created eight crossbred treatments: A-AA (n=10), A-AF (n=9), A-AJ (n=10), A-AK (n=5), S-AA (n=11), S-AF (n=3), S-AJ (n=11) and S-AK (n=5). Live weight between 329 days of age and slaughter, and ultrasoundderived and slaughter-day carcass characteristics were measured. At 400 and 600 days of age, respectively, Simmental-sired steers were 22 kg and 37 kg heavier than Angus-sired steers (P<0.05). All steers had a similar intramuscular fat percentage (P>0.05). Simmental-sired steers had greater eye-muscle area than Angus-sired steers (P<0.05). Simmental-sired steers had heavier and longer carcasses, and greater dressing-out percentages than Angus-sired steers (P<0.05). Simmental sires produced fast-growing progeny with heavier carcasses than Angus sires for all dam lines. Angus-cross-dairy cows produced steer progeny with similar carcass characteristics to those from Angus cows bred with beef bulls.

How do you build a profitable beef cowherd? - Leachman L (Proceedings of the New Zealand Society of Animal Production, 2015)

The influence of hogget liveweight change during their first lactation on pregnancy rates at the subsequent breeding period - Corner-Thomas RA; Morris ST; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2015)
Breeding ewe lambs can have a negative effect on subsequent two-tooth breeding weights which may impact on subsequent reproductive rates. The impact of ewe lamb breeding can be alleviated by providing ewes with forages with high nutritive value such as lucerne or a herb mix such as chicory, plantain, red clover and white clover. In a study conducted over two breeding seasons ewe lambs were offered a ryegrass and white clover pasture, a herb mix or lucerne from one week prior to the expected start of lambing until weaning. The impact liveweight change during lactation, and from weaning until breeding as a two-tooth, on pregnancy and fecundity rates was examined

The lying behaviour of non-lactating, pregnant dairy cows wintered in a loose-housed barn on woodchip bedding material - Davison LJ; Dalley DE; Chrystal J; Monaghan R; Laurenson S; Stevens D; Wall A; Pigou J; Gorton A (Proceedings of the New Zealand Society of Animal Production, 2015)
Winter represents an important time for dairy herds in the southern South Island of New Zealand. In an attempt to address poor performance in forage crop-based wintering systems, farmers are increasingly using off-paddock methods of wintering, such as housing their cows in barns. The aims of this study were to monitor the lying behaviour of cows wintered in a loose-housed barn with woodchip bedding during three separate seven day periods to determine (i) if recommended lying times were being met, and (ii) if bedding moisture content could be used as a predictor of lying time. Twenty-one non-lactating dairy cows were selected, based on age, body condition score and stage of pregnancy, from a housed herd of 90 mixed-age cows. Lying and standing movements were recorded at thirty second intervals using an electronic movement data logger attached to the ankle of each cow. Monitoring in Period 1 commenced four days after the cows entered the barn for wintering in early June; Period 2 occurred in early July, just prior to the removal and replacement of bedding material, and Period 3 occurred in mid-July when cows were again on fresh bedding material. Average daily lying times were two hours longer during Periods 1 and 3, when barn material was fresh (10.7 and 10.5 h/day, respectively), than when soiled during Period 2 (8.4 h/day). The difference in lying behaviour was due to a difference in the number of lying bouts: cows had fewer lying bouts during Period 2 (6.1 per day) than Periods 1 & 3 (7.4 and 7.9 per day, respectively). The average moisture content of the bedding was 60.7, 68.4 and 64 .3 % for Periods 1, 2 and 3, respectively. Bedding moisture content per se did not appear to be a good predictor of lying time, suggesting other factors such as bedding temperature and cleanliness and stage of pregnancy were influencing lying behaviour. These results are discussed in relation to bedding surface management and the welfare of housed dairy cows.

Milk production and urination behaviour of dairy cows grazing diverse and simple pasture - Edwards GR; Bryant RH; Smith N; Hague H; Ferris A; Farell L (Proceedings of the New Zealand Society of Animal Production, 2015)
Milk production and urination patterns were measured for mid-lactation dairy cows grazing a simple perennial ryegrass-white clover pasture (n = 15) and a more diverse pasture (n = 15) containing herb (chicory and plantain) and legume (lucerne) species in addition to the perennial ryegrass and white clover. Milksolids production was similar for simple (2.09 kg MS/cow/d) and diverse (1.94 kg MS/cow/d) pasture. Urination volume and frequency were similar for simple (2.0 L/urination, 11.6 urinations/cow/d) and diverse (2.2 L/urination, 15.0 urinations/cow/d) pasture. Urine-nitrogen (N) concentration was 20% lower for diverse (4.9 g N/L) than simple (6.1 g N/L) pasture. Diverse pastures may offer benefits for reducing the environmental impact of dairy farming by reducing the N loading of urine patches.

Modelling the effect of more lambs, faster growth and heavier carcasses on feed conversion efficiency and seasonality of demand - Klaassen PL; Woodford KB; Trafford GM (Proceedings of the New Zealand Society of Animal Production, 2015)
Feed conversion efficiency (FCE) and seasonality of feed demand were assessed within a demand-driven deterministic steadystate model of a sheep livestock system. Weekly animal feed demands were simulated within ExcelTM. Overall flock structure and seasonality of demand were then determined using linear programming. Key inputs were individual animal energy requirements (MJME) for maintenance, pregnancy, lactation and growth. Whole-of-system FCE was measured as grams of meat carcass per MJME. Overall system output was constrained by a fixed but arbitrary system limit of 10 million MJME. Increasing the lambing percentage from 110% to 170% increased FCE by 20%, with less total system feed required during the pregnancy period but with more feed required post-weaning. Increasing pre-weaning liveweight gain from 250 g/day to 450 g/day increased FCE by only 1%, but with a transfer of feed demand from post-weaning to pre-weaning. Increasing post-weaning liveweight gain from 100 g/day to 300 g/day increased FCE by 8% with earlier slaughter reducing overall post-weaning requirements. Increasing carcass weight from 12 kg to 24 kg increased FCE by 28%, with a major shift in feed demand from pre-weaning to post-weaning. Implications for improving pastoral sheep farm productivity and profitability are discussed.

New Zealand case studies of automatic-milking-systems adoption - Woodford KB; Brakenrig MH; Pangborn MC (Proceedings of the New Zealand Society of Animal Production, 2015)
Case studies were undertaken of six New Zealand farmers who have adopted automatic milking systems (AMS). Data were collected during spring 2014. Farmer experience with AMS ranged from one to four years. Three farms were in the Waikato and three were in Canterbury. Two farms use barns with fully-confined cows, two use pasture-based systems with year-round pasture access, and two use hybrid systems where cows confinement for varying times depending on season. The key focus was on documenting farmer experience. All six farmers met innovator criteria and were driven by the challenge of making the system work. Farmers reported per cow production above their previous dairying experience and expectations. Cows-per-robot ranged from 50 to 80 and were higher on pasture systems where daily milkings per cow were lower relative to confined systems. Annual milksolids production ranged from 30,000 to 42,900 kg per robot. Total labour requirements did not always change but the type of labour did change. Initial training of cows was stressful for farmers and time consuming. Farmers emphasised that it was a total change of system requiring new ways of thinking. Farmers perceived capital cost as the major adoption constraint but remained positive about the future of AMS.

New Zealand Society of Animal Production – The Past 25 Years - Nicol AM (Proceedings of the New Zealand Society of Animal Production, 2015)

Nitrogen partitioning in sheep offered three perennial ryegrass cultivars at two allowances in spring and autumn - Jonker A; Cheng L; Edwards GR; Molano G; Taylor PS; Sonoval E; Cosgrove GP (Proceedings of the New Zealand Society of Animal Production, 2015)

Phenotypic correlations among alternative definitions of feed efficiency in grazing lactating dairy cows across parities and lactation stages - Hurley AM; Lopez-Villalobos N; McParland S; Lewis E; Kennedy E; O'Donovan M; Burke JL; Berry DP (Proceedings of the New Zealand Society of Animal Production, 2015)
The objective of this study was to estimate correlations among alternative measures of energy conversion efficiency and energy balance (EB) across parities and lactation stages in grazing lactating dairy cows. Individual measurements of net energy intake (NEI) (n=8,183) from pasture and concentrate from 2,693 lactations on 1,412 cows were available. Residual energy production (REP) was defined as net energy of lactation (NEL) minus predicted energy requirements; energy conversion efficiency (ECE) was defined as NEL divided by NEI; and EB was defined as the difference between NEI and energy required for both maintenance and lactation. Residual energy intake (REI) was defined as NEI minus predicted energy requirements. A strong correlation existed between REI and EB (0.88; P<0.05) for parity three or greater early lactation, weakening in parity one (0.70; P<0.05). These differences in correlations between REI and EB for animals across parities in early lactation, indicated primiparous animals were using body energy for milk production and growth; nevertheless, these strong correlations suggested negative REI animals (i.e., more efficient) are also in more-negative EB. Our findings suggest REI could be a valuable tool for future genetic improvement,

Preliminary linkage studies in sheep of keratin and keratin-associated protein genes with fleece weight, wool fibre diameter and fibre curvature - Phua SH; Scobie DR; O'Connell D; Henry H; Dodds KG; Brauning R; Clerens S (Proceedings of the New Zealand Society of Animal Production, 2015)
A linkage study was conducted to detect variations in the genes for keratins and keratin-associated proteins (KRTAP) that might affect wool traits. To date 93 such genes have been identified in sheep: 85 of them (~91%) are clustered in three chromosomal regions. Twenty-one genes are grouped within a 4-Mbp region on sheep chromosome 1 (OAR1), 28 within a 1-Mbp segment on chromosome 3 (OAR3), and 36 are clustered within a 1.3-Mbp site on chromosome 11 (OAR11). The DNA markers used in this work were single nucleotide polymorphisms (SNPs) dispersed throughout these keratin and KRTAP gene clusters. Markers were designed as three SNP-multiplexes: a 25-SNP, a 15-SNP and a 19-SNP multiplex for keratins/KRTAP regions on OAR1, OAR3 and OAR11, respectively. Resource animals came from eleven sire families whose progeny had been phenotyped for greasy fleece weight, washing yield, fibre curvature and diameter. Between 29 and 45 progeny per sire were genotyped with the three SNPmultiplexes. Linkage analyses on co-segregation of SNP alleles from sires with wool phenotypes of progeny were done across all the sires and within sire groups. Based on theoretical genome-wide threshold (F-value 10.13 and nominal P = 0.0016 for withinsire suggestive level), one family showed suggestive quantitative trait loci for greasy fleece weight on OAR1 and fibre diameter variability on OAR3. For these experimental animals, the results show no strong evidence of involvement of keratin and KRTAP genes in the wool characteristics analysed.

Presidential Address 2014: The role of the New Zealand Society of Animal Production in the era of digital networks - Pacheco D (Proceedings of the New Zealand Society of Animal Production, 2015)

The reasons farmers choose to dock lamb tails to certain lengths, or leave them intact - Kerslake JI; Bryne TJ; Behrent MJ; Maclennan G; Martin-Collado D (Proceedings of the New Zealand Society of Animal Production, 2015)
Compared to a survey carried out in 2005, New Zealand farmers appear to be docking fewer lamb tails flush (6% vs. 22%) and docking a greater number of lamb tails at 4-7 cm length (32% vs. 16%). The main reasons for docking were to minimize fly strike risk, reduce accumulation of dags and keep the crutching costs down. Farmers who docked lamb tails to a shorter length (3-4 cm) gave significantly (P<0.05) more importance to minimizing fly-strike, reducing the likelihood of dags and reducing the cost of crutching than any other reason. Farmers who docked lamb tails at a longer length (4-7 cm) gave significantly (P<0.05) more importance to meeting the processor requirements, minimizing euthanasia from uterine prolapse and minimizing fly-strike risk than any other reason. When farm performance characteristics, that may influence decisions relating to tail docking practices, were prioritised by farmers, preferences for minimizing deaths from fly-strike, improving weaning weight and making more money from the processor were greater than having fewer dag events, less euthanasia from rectal prolapses and less stress for the lamb at docking. These preferences did not differ among farmers that dock tails at different lengths or leave them intact.

Relationships among skin thickness, fat depth and eye muscle depth in sires and their progeny, and the breeding value for survival of their progeny - Tait IM; Hickson RE; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2015)
Lamb survival to weaning is an important determinant of farmer income and an animal welfare issue. The aim of this study was to determine whether skin thickness, fat depth and eye muscle depth (EMD) of the sires were related to skin thickness, fat depth, EMD and survival estimated breeding value (eBV) of their progeny. Data from a total of 19,436 lambs born between 2010 and 2013 inclusive were obtained from four farmers who comprise the Terminal Romneys for Increased Genetic Gain (TRIGG) group. Records included weaning weight, flock, sex, birth rank, date of birth, dam identity, sire identity and live weight at ultrasound measurement; skin thickness, fat depth and EMD measured using ultrasound at eight-months of age; and the survival eBV. Heritabilities for weaning weight, skin thickness, fat depth and EMD were 0.60±0.08, 0.21±0.07, 0.25±0.08 and 0.61±0.23 respectively. Skin thickness and EMD of the sire were positively correlated with progeny survival eBV while sire fat depth was negatively correlated with lamb survival eBV. Skin thickness, EMD and fat depth showed promise as indirect selection criteria for improved lamb survival. Additional data are required to confirm this.

Remote sensing of heart rate and rumen temperature in feedlot beef cattle: associations with feeding and activity patterns - Munro JC; Schenkel FS; Miller SP; Tennessen T; Montanholi YR (Proceedings of the New Zealand Society of Animal Production, 2015)
Heart rate (HR; beats/min) rumen temperature (RTMP; ºC), activity level (ACT; %) and feeding patterns (feeding event duration; sec/30 min, feed intake; kg/30 min, visits to the feeder; visits/30 min) have been suggested as feed efficiency (residual feed intake; RFI; kg/d), distress and health status indicators in cattle holding potential for development into practical on-farm decision making tools. Our study assessed the associations between these parameters when feedlot cattle (n=22) were eating or not eating (FI dataset), at differing activity levels (ACT dataset) and between feed efficient and feed inefficient cattle (RFI dataset). Heart rate was not different between FI, ACT and RFI groups. RTMP was lower in high ACT then low ACT observations (39.64±0.15 vs 40.08±0.15; P=0.001) and was associated with ACT in positive RFI cattle (r=-0.55; P <0.001). Activity levels in the ACT dataset were lower when cattle were located in the yard then when located in the pen or abattoir. Associations between RTMP and ACT across ACT and RFI datasets promote these as potential indicators of feed efficiency and health status in cattle. Changes in ACT across locations suggest it to be a potential indicator of distress. Future studies assessing RTMP and ACT abilities to determine performance are warranted.

Ryegrass staggers and liveweight gain of ewe lambs and hoggets grazing four combinations of perennial ryegrass and strains of endophyte - Logan CM; Edwards GR; Kerr GA; Williams S (Proceedings of the New Zealand Society of Animal Production, 2015)
Ryegrass staggers and live weight gain of Coopworth ewe lambs or hoggets were assessed over four eight week trials (two summer, two autumn) for four combinations of perennial ryegrass and strains of endophyte: Arrow with standard (SE, wild type) endophyte, Trojan with NEA3 endophyte, Trojan with a mixture of NEA2 and NEA3 endophytes, and Rohan with a mixture of NEA2 and NEA6 endophytes. In each trial, three replicates of 10 to 12 sheep were assigned to 0.3 ha plots of each cultivar x endophyte strain combination, with herbage mass reduced from 3-4000 kg DM/ha to 1500 kg DM during the eight weeks. Severe ryegrass staggers occurred in all four trials in Arrow SE, with a mean ryegrass staggers score ranging between 1.65 to 2.8 (0 to 5 scale). Minor ryegrass staggers occurred in Trojan NEA3, Trojan NEA2/3, Rohan NEA2/6 in two of the four trials, but only with a low mean score (<0.4). Live weight gain was lower in Arrow SE than the other cultivars in three of the four trials. Trojan NEA3 had live weight gain that was different from Trojan NEA2/3 (+27 g/head/day higher in Trojan NEA2/3) on one trial only. The perennial ryegrass cultivar x novel endophyte strain combinations Trojan NEA3, Trojan NEA2/3 and Rohan NEA2/6 showed liveweight gain that was similar or greater than the standard endophyte control, and caused minimal ryegrass staggers in ‘worstcase scenario’ conditions designed to induce this.

The sheep dairy industry in New Zealand: a review - Peterson SW; Prichard C (Proceedings of the New Zealand Society of Animal Production, 2015)

A snapshot of New Zealand farmers’ awareness of, and self-reported compliance with, animal welfare requirements - Williams VM; Pearson AB; Jeffrey GB; Mackenzie RW; Ward LJ; Fisher MW (Proceedings of the New Zealand Society of Animal Production, 2015)
A 2012 telephone survey of 1565 farmers from across pastoral, pig and poultry livestock sectors aimed to benchmark farmer awareness of and self-reported compliance with the Animal Welfare Act 1999 and codes of welfare, and to explore the factors that drive or hinder that compliance. Eighty-two percent of respondents assessed their knowledge of statutory animal-welfare requirements as above average or excellent. However, of the five physical, health and behavioural needs of animals on which the legislation is based, only proper and sufficient food and water and adequate shelter were identified by more than half of respondents (77% and 54%, respectively). Once informed of the needs, 63% considered it not difficult to provide for all five. The majority of respondents reported levels of compliance with statutory animal-welfare requirements above 85% and knew of relevant examples of minimum standards from a code of welfare. The main barriers to providing for the needs of animals were identified as seasonal weather conditions [pastoral enterprises] and lack of money or resources [within the pork and poultry sectors]. In conclusion, while identification of statutory animal-welfare requirements was not high, farmers do understand the concepts that underpin the legislation.

Stayability of beef-cross-dairy breeding cows to six years of age - Hickson RE; Corner-Thomas RA; Martin NP; Kenyon PR; Lopez-Villalobos N; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2015)
The use of dairy-beef crosses is widespread throughout the New Zealand beef industry. Cattle originating from dairy herds make up 50 – 55% of New Zealand beef exports by weight (Morris & Kenyon 2014). However, there is little information available regarding the use of beef-cross-dairy cows as breeding cows in terms of reproductive success and stayability in the herd. A study was conducted to investigate the pattern of cow culling and stayability from eight months of age until marking of the fifth calf of straight-bred Angus and Angus-cross-Friesian, Angus-cross-Jersey and Angus-cross-Kiwicross cows. The results showed that the stayability of these breeding cows was low, however, there were no differences in the stayability of straight-bred Angus or beefcross- dairy cows.

Transfers of genetic merit through multiple-tiered breeding structures into trait expressions for commercial sheep production - Santos BFS; Byrne TJ; Amer PR; Gibson JP; Van der Werf JHJ (Proceedings of the New Zealand Society of Animal Production, 2015)
In New Zealand, selection of both replacement females and sires based on performance is typically highly rudimentary in multiplier and commercial flocks. Selection of ewes and rams in these tiers is frequently driven by soundness and overall condition of selected animals and sometimes, based on whether or not the replacement candidate was born in a multiple litter. In breeder flocks, selection is usually supported by knowledge of the genetic merit of candidates. In multi-tiered breeding schemes, genetic progress is disseminated from the nucleus to the commercial tier through the transfer of males. Gene-flow principles can be applied in the optimization of multi-tiered breeding schemes, particularly to define the proportion of genetic superiority expressed in an individual, which also gets expressed in its descendants, in time, across tiers. The opportunity to increase the rate of progress and reduce the genetic lag between tiers in integrated production systems might be exploited by selecting candidates from which performance of the progeny can be predicted. The results of this simulation study demonstrate the long time delays of up to 25 years for genetic expressions to fully flow through a multiple-tiered breeding scheme. There was long time delay before genetic progress realised in the nucleus was achieved in the commercial flocks. For example, it was approximately fourteen years until 70% of benefits of genetic improvement in lambing and slaughter traits were captured in the commercial flocks. This delay was mitigated when performance recording was implemented in the multiplier flock. This gain however, does not have the permanent and cumulative properties of genetic progress achieved in the nucleus flock, and so needs to be continued each year for the benefits to be maintained.

Uncovering genetic variation in cow fertility using simulation - Dennis NA; Stachowicz K; Visser B; Hely FS; Amer PR; Meier S; Burke CR (Proceedings of the New Zealand Society of Animal Production, 2015)
Dairy cow fertility is currently measured using two traits: the proportion of cows mated within 21 days of the start of mating (PM21) and the proportion of cows that calve within 42 days of the start of calving (CR42). These traits indirectly measure a cow’s genetic propensity to return to a fertile state after calving. Both PM21 and CR42 have low heritability (0.05 and 0.03, respectively) and fertility is suspected to have much stronger genetic drivers than indicated by these lowly heritable components. The purpose of this study was to explore genetic and environmental factors that contribute to dairy cow fertility using a stochastic simulation model. The model traces the reproductive life of cows from birth until their second calving date using environmental and genetic variables to simulate fertility phenotypes. The model demonstrated that even when significant genetic variation was simulated in underlying fertility traits, this variation appears only weakly as genetic effects using the current fertility traits evaluated for genetic selection purposes. Potential alternative traits (e.g. gestation length, heifer puberty trait, strength of oestrus expression or post-partum anoestrous interval) were shown to have potential to add value when identifying sires whose daughters calve earlier in the season.

Urinary nitrogen excretion, grazing and urination behaviour of dairy heifers grazing pasture, chicory and plantain in autumn - Cheng L; McCormick J; Hussein AN; Fraslin C; Moonsan Y; Moonsan P; Logan C; Grabot J; Edwards GR (Proceedings of the New Zealand Society of Animal Production, 2015)
The objective of this study was to investigate urinary nitrogen (N) excretion, grazing and urination behaviour of dairy heifers grazing pasture, chicory and plantain. A 35-day trial was conducted with 56 Friesian x Jersey heifers aged 9-10 months. Heifers were blocked into five treatments balanced for their live weight and breeding worth: 100% ryegrass/white-clover pasture (PA; n = 12); 100% chicory (CH; n = 10); 100% plantain (PL; n = 12); 50% pasture + 50% chicory (PA+CH; n = 10); and 50% pasture + 50% plantain (PA+PL; n = 12). Feed was offered every three days with allowance calculated according to feed requirement for maintenance plus live weight gain of 0.8 kg/day. Measured urinary-N concentration, estimated daily urinary-N excretion (UN) and urinary output were similar among treatments. During the first six hours after feed allocation, heifers spent more time idling and less time ruminating on CH and PL than on PA. The CH and PA+CH groups urinated more frequently than other groups. Data from this study indicate that heifers grazed chicory urinated more frequently without increasing daily UN and may potentially reduce N loading from soil. Future study is needed to take account of urinary N excretion diurnal variation.

Use of a urine meter to detect variation in urination behaviour of dairy cows on winter crops - Ravera BL; Bryant RH; Cameron KC; Di HJ; Edwards GR; Smith N (Proceedings of the New Zealand Society of Animal Production, 2015)
Nitrate leaching loss from urine patches is predicted using a number of variables including urine N concentration, number of urine patches produced, and urine patch size however, there is a lack of quantitative data on the variability of urination events. A study was conducted using two wintering systems at Ashley Dene, Lincoln, between June and July 2014. Wintering systems were either kale (KA) fed at an allowance of 14 kg DM/cow/day plus barley straw (3 kg DM/cow/day) (n=5), or fodder beet (FB) fed at an allowance of 8 kg DM/cow/day, plus ryegrass baleage (6 kg DM/cow/day) (n=7). Twelve pregnant, non-lactating Holstein- Friesian x Jersey cows were fitted with calibrated urine meters which measured volume and frequency of urination events. The meters were worn for 24-hour periods. A calibration equation was used to calculate urine patch coverage from measured urine patch areas in the field and urine volumes. There was large variation between animals for urination behaviour. Average urination volume was similar for KA and FB (2.37 L/event; P>0.1 SEM=0.29), however urination frequency (12 vs. 8 events/day; P<0.1 SEM=2.25) and daily total urine volume (30 vs. 18 litres; P<0.03, SEM=4.56) were greater for KA. Average urine patch area was also 1.8 times larger on KA than on FB (0.47 vs. 0.25 m2). This information will be used to help predict nitrate leaching losses from grazing systems.

The use of herb mix and lucerne to increase growth rates of dairy heifers - Handcock RC; Hickson RE; Back PJ (Proceedings of the New Zealand Society of Animal Production, 2015)
Approximately 53% of 6-month-old dairy heifers in New Zealand do not meet liveweight targets, partially due to inadequate growth rates in their first summer. The aim of this experiment was to determine the effect of feeding forage crops on the growth rate of dairy heifers over this critical period. Sixty six-month-old dairy heifers grazed one of three treatments: pasture, lucerne or a mixed-herb crop for a 63-day period. Both lucerne- and crop-fed heifers had similar (P>0.05) average daily liveweight gain (0.80 ± 0.02 and 0.75 ± 0.02 kg/day, respectively) and were greater (P<0.05) than those of pasture-fed heifers (0.53 ± 0.02 kg/ day). Lucerne-fed heifers had a greater (P<0.05) increase in body length (18.4 ± 1.3 cm) than heifers fed pasture (14.7 ± 1.2 cm). Heifers fed lucerne had higher (P<0.05) concentrations of urea in plasma (4.9 ± 0.1 mmol/L) compared with heifers fed crop (4.1 ± 0.1 mmol/L), which had greater (P<0.05) concentrations of urea in plasma than heifers fed pasture (2.5 ± 0.1 mmol/L). Feeding a mixed-herb crop or lucerne during the summer period resulted in higher growth rates of dairy heifer calves compared with feeding them pasture.

Using polymerase chain reaction to identify Streptococcus uberis in bovine milk: how does it compare with bacterial culture? - Steele NM; Williamson JH; Laven RA; Hillerton JE (Proceedings of the New Zealand Society of Animal Production, 2015)
Rapid identification of the pathogen responsible for an intramammary infection in a dairy cow can support herd management decisions. Polymerase chain reaction (PCR) has become available to identify mastitis pathogens in milk, offering a rapid and sensitive test. The performance of a commercial, real-time PCR assay was compared with traditional bacterial culture for the identification of the most-frequent pathogen in New Zealand, Streptococcus uberis, during three stages of lactation. Aseptically collected quarter-milk samples (n=6,848) were analysed by culture, and a subset (n=315) selected for PCR analysis based on S. uberis infection status. Using culture as the reference test, PCR had a relative sensitivity of 89.0%, and a specificity of 64.3% (kappa=0.49) for detecting S. uberis in milk collected at the first milking post-calving. The relative sensitivity and specificity for samples collected in mid-late lactation were 89.3% and 97.7%, respectively, indicating a greater agreement between the two tests later in lactation (kappa=0.88). Accurate diagnostic tests are necessary for mastitis management. In early lactation, when S. uberis prevalence is high, bacterial culture should be used. The PCR assay tested in this study is most useful after the first month of lactation.

Alternative forages for livestock production - Morris ST; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2014)
In the New Zealand sheep, dairy and beef cattle industries, pastures are predominantly perennial ryegrass-white clover with some brassica and maize crops grown. There has, however, been increased interest in pure swards of alternative legumes such as lucerne and red clover, or forage herbs such as plantain and chicory.

Alternative method to measure herbage dry matter (DM) mass in plantain and chicory mixed swards grazed by lambs - Somasiri SC; Kenyon PR; Morel PCH; Kemp PD; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2014)
Calibration equations are available to determine the dry matter (DM) mass of pasture using either sward height or plate meter readings. Currently there are no methods available for determining DM in a herb-clover mix other than using quadrat cuts. The objective of this research was to determine the relationships between herbage DM mass as measured by quadrat cuts vs sward height and plate meter readings for herb-clover mixes during four seasons from early spring to autumn. Pre- and post-grazing herbage DM masses (kg/ha) in the plantain mix (plantain (Plantago lanceolata), white clover (Trifolium repens) and red clover (T. pratense)) and in the chicory mix (plantain, chicory (Cichorium intybus), white clover and red clover) were estimated by collecting quadrat cuts. For each quadrat cut, a plate meter reading and five sward height measurements were also recorded. Separate regression equations were then developed for quadrat herbage DM mass vs sward height and plate meter readings. In addition, data from the plantain and Chicory mixes were pooled to obtain a data set for a combined herb-clover mix. The individual R 2 values were significant for all three relationships and ranged from 0.49 to 0.86. The concordance correlation coefficient (CCC) for all three relationships fell between 0.56 and 0.94. The relative prediction error (RPE) for all three relationships varied between 18 and 29%. The regression equations developed by these non destructive methods, would enable farmers to obtain a reliable estimate of the herbage DM mass, with a level of precision sufficient for making day-to-day grazing management decisions on farm. The data do suggest different regression equations need to be utilised for different seasons of the year.

Assessing the meat quality of venison short-loin from farmed red deer using visible-near infrared spectroscopy - Craigie CR; Purchas RW; Maltin CA; Roehe R; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2014)
Venison from red deer (Cervus elaphus) is marketed as a premium quality, healthy red meat. Ideally, meat-quality attributes need to be measured prior to sale. Near infrared spectroscopy (NIRS) has potential for the measurement of sensory, nutritional and technological parameters in beef, but its use on venison has not yet been considered. The aim was to evaluate NIRS for predicting Warner-Bratzler shear-force parameters, meat colour, ultimate pH, sarcomere length and water holding capacity of venison short-loins. Samples were halved, vacuum packaged, aged for either 3 or 42 d at 1±1°C and frozen, then defrosted for meat-quality assessment and acquisition of spectral data. In total, 154 samples (3 and 42 d aged) were divided into calibration (75%) and validation datasets (25%). Using partial-least squares regression, calibration equations were tested on the validation dataset. Prediction accuracies ranged from R2 =8.3%, (SEpred =2.42) for meat lightness to R2 =66.6%, (SEpred =0.10) for ultimate pH, suggesting that NIRS maybe useful for predicting some venison quality parameters.

BRIEF COMMUNICATION: An evaluation of the sensory traits of venison - Mathias-Davis HC; Ward JF; Dodds KG; Everett-Hincks JM; Maclennan G (Proceedings of the New Zealand Society of Animal Production, 2014)
New Zealand venison is a well-regarded export product in Europe and quality is a key philosophy of the deer industry. As production targets increase understanding consumer preferences is important to ensure the eating quality of venison is maintained alongside these goals. Using data available from the Deer Progeny Test (Ward et al. 2014) this study aims to assess the quality of data from a sensory evaluation and investigate relationships between sensory traits and the overall acceptability of venison...

BRIEF COMMUNICATION: An exploratory investigation of the effects of selection for divergence in methane emissions on rumen digesta and carcass traits in 8-month old sheep - Elmes SN; Bain WE; Greer GJ; Hickey SM; Young EA; Pickering NK; Rowe SJ; Knowler KJ; Pinares-Patiño CS; McEwan JC (Proceedings of the New Zealand Society of Animal Production, 2014)
Global agriculture accounts for approximately 14% of anthropogenic emissions. In New Zealand, methane emissions from ruminants comprise 31.5% of the total emissions (Ministry for Environment 2009), therefore, any future mitigation of emissions could have substantial economic implications for the agricultural sector. Reducing emissions from ruminant livestock without affecting animal production against a rising demand for animal products is challenging (Clark 2009). Measurements carried out over the last 15 years have shown a common feature of individual animal variation in methane emissions (Pinares-Patiño et al. 2011b). Recently it has been shown that enteric methane emissions from sheep are both heritable and repeatable (gCH4/day 0.29 ± 0.05; repeatability 0.26 ± 0.02), whether expressed as gross emissions (g/d) or methane yield (emissions per unit of feed dry matter intake, g/kgDMI; Pinares-Patiño et al. 2013). This makes breeding an attractive mitigation strategy for the lowering of enteric emissions from ruminant livestock given animal production performance is not affected (Pinares-Patiño et al. 2011a)...

BRIEF COMMUNICATION: Analysis of the on-farm cost of ovine pleurisy - Hickford JGH; Hodge S; Bates JR; Hogan AK (Proceedings of the New Zealand Society of Animal Production, 2014)
Pleurisy is the result of an inflammation of the pleura producing fibrous adhesions between the lung and chest wall. In New Zealand (NZ) sheep, it has a substantial impact in terms of lost revenue, animal health and welfare, and in 2006 its cost was estimated at NZ$25.1 million (95% CI=NZ$10.2–48.1; Goodwin-Ray et al. 2008). Little is known about how to diagnose the disease prior to slaughter, although a NZ sheep industry report (Goodwin-Ray 2006) describes a “pneumonia-pleurisy complex”, based on the findings of McGowan et al. (1978), Davies (1985) and Pfeffer (1986). Goodwin-Ray (2006) concludes that this complex has a poorly defined aetiology, likely reflecting the observation by McGowan et al. (1978) that some, but not all lambs with enzootic pneumonia, went on to develop pleurisy. In effect there is no evidence of an absolute link between pneumonia and pleurisy

BRIEF COMMUNICATION: Are fetal programming effects, due to maternal early pregnancy nutrition, evident in adult male offspring in sheep? - Pain SJ; Asmad K; Fermin LM; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2014)
Manipulation of fetal development processes via maternal nutritional intervention can affect the physiology and cellular function of adult offspring through a process known as fetal programming (Harding & Johnson 1995). Nutritional status of the dam in the first trimester of pregnancy is crucial to fetal development because, although fetal energy requirements in early pregnancy are relatively small, and thus, total nutrient demand is typically low, fetal metabolic activity is very high and organogenesis is occurring (Harding & Johnson 1995)...

BRIEF COMMUNICATION: Comparison of early embryo development in Cheviot and Suffolk breeds of sheep - Fermin LM; Pain SJ; Blair HT; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2014)
Maternal constraint is the major non-genetic factor determining the size of the fetus at term (Gluckman & Hanson 2004). Previous studies in various animal models have reported the effect of maternal size on birth size and postnatal growth, (Allen et al. 2002; Gardner et al. 2007) whereby fetal development and birth weight are reduced in a restricted maternal uterine environment, while enhanced in a luxurious uterine environment...

BRIEF COMMUNICATION: Dairy Extension - Payne MS (Proceedings of the New Zealand Society of Animal Production, 2014)
Growth has characterised the dairy industry since the 1990s. From 1992 to 2012 the industry doubled its occupation of total grasslands in New Zealand and increased cow numbers to be on par with the national population. Almost half of all stock units in this country are now dairy cows. ...

BRIEF COMMUNICATION: Developmental programming in sheep due to early pregnancy nutrition alters milk yields of adult female offspring but not of grand-offspring - Peterson SW; Pain SJ; Jenkinson CMC; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2014)
Two long-term studies by our group have shown that nutrition of the pregnant dam altered the growth and development of the ewe offspring, and their subsequent lactational performance (van der Linden et al. 2009; Paten et al. 2013a). These effects were attributed to developmental programming possibly via epigenetic changes. Epigenetic regulation, such as histone modifications and chromatin condensation, has been implicated in the short- and long-term control of transcription in mammary epithelial cells (Kress et al. 2010)...

BRIEF COMMUNICATION: Does feeding level of ewe lambs affect their response to vasectomised rams? - Kenyon PR; Viñoles C; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2014)
Exposure of ewe lambs (also known as hoggets or yearlings) to vasectomised rams (teasing) has increased breeding activity early in the breeding period in some but not all studies (Hudgens et al. 1987; Kemp et al. 1991; Ungerfled 2007; Cave et al. 2012; Kenyon et al. 2012, 2014). Additional effects reported include increased overall pregnancy rates and number of foetuses per ewe lamb (Kenyon et al. 2014). It would be of benefit if the cause of the variation among studies in the ewe lamb response to teasing could be identified. In mature ewes, nutrition has been reported to influence the teasing response when it is used to advance the breeding season (Scaramuzzi & Martin, 2008). Therefore, the present study aimed to test the hypothesis that ewe lambs offered an unrestricted level of pastoral nutrition would have an enhanced response to teasing.

BRIEF COMMUNICATION: Effect of early life diet on lamb growth and organ development - Danso AS; Morel PCH; Kenyon PR; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2014)
Neonate lambs are pre-ruminants until approximately 3 – 4 weeks of age (Treacher & Caja 2002) and therefore their dam’s milk is key to their survival and growth. During this period, their digestive system is relatively immature. Attempts have been made to evaluate the effects of early weaning on lamb growth performance with few data available at ages earlier than 4 weeks (Brown 1964; Large 1965; Walker & Hunt 1981; Lane et al. 1986). These early studies show that lambs can be weaned at two to three weeks of age, however, they often result in growth rate checks. These findings suggest lambs require liquid diet for a minimum of two to three weeks. Nevertheless, rumen development is essential to enable lambs continue a normal growth trajectory when milk consumption ceases (Poe et al. 1969). Our objective was to examine the impacts on lamb growth and organ development when pellets are added to the milk diet of lambs in very early post birth life. Furthermore, lamb growth rates have improved by 50 g/day since the 1980s (Bray 2004). This may imply that the efficiency of lambs in utilising energy in their diet for growth and maintenance has altered. Thus, in addition to the growth performance, the utilisation of metabolisable energy (ME) in the diet for maintenance and growth was also examined.

BRIEF COMMUNICATION: Ewe ultra-sound pregnancy diagnosis and its use by New Zealand farmers - Corner-Thomas RA; Kenyon PR; Morris ST; Ridler AL; Hickson RE; Greer AW; Logan CM; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2014)
Ultra-sound pregnancy diagnosis can be a valuable management tool for sheep farmers. The benefits include early identification of non-pregnant (dry) ewes which can be culled, freeing up valuable feed for pregnant ewes (Blair 1986) and the identification of single, twin and triplet fetuses, allowing ewes to be fed based on their specific nutritional requirements during pregnancy (Garrick 1998). In addition, selection of lambing paddocks can be made based on the number of fetuses identified (Garrick 1998).

BRIEF COMMUNICATION: Farmer Learning and Extension – The Beef + Lamb New Zealand Approach - Wakelin R; Champion S (Proceedings of the New Zealand Society of Animal Production, 2014)
While the sheep and beef sector has faced considerable challenges over recent times, it remains New Zealand’s second largest primary industry and export sector, contributing over $7 billion to the New Zealand economy each year. Importantly, the Red Meat Sector Strategy (RMSS), released in May 2011, defined a suite of initiatives that could be employed to grow the sector’s economic contribution, and also to improve the profitability of all participants in the red meat value chain...

BRIEF COMMUNICATION: FarmIQ - Learning and extension around quality meat production - White T (Proceedings of the New Zealand Society of Animal Production, 2014)
FarmIQ was established in August 2010,following a successful bid to the Ministry for Primary Industries’ Primary Growth Partnership (PGP) fund. The partnership is between MPI and three significant farming industry entities – Silver Fern Farms (SFF), Landcorp Farming Limited and Tru-Test Group.

BRIEF COMMUNICATION: Genetic evaluation for milking performance in a large flock of milking sheep in New Zealand - McMillan WH; McLachlan SJ; Hercus IS; Lopez-Villalobos N (Proceedings of the New Zealand Society of Animal Production, 2014)

BRIEF COMMUNICATION: Grand-dam age has no effect on ram lamb live weight and carcass characteristics - Burnham DL; Kenyon PR; Pain SJ; Hickson RE; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2014)
Breeding ewe lambs at 7 to 9 months of age can increase their lifetime productivity and profitability (Young et al. 2010; Kenyon et al. 2011, 2014). Further, in theory, increased genetic gain can be made from selecting progeny born to ewe lambs as replacement ewes. However, little is actually known about the long-term phenotypic impacts of such a management option. Loureiro et al. (2012) examined the reproductive and lactational performance of 18-month-old ewes born to either ewe lambs or mature ewes and reported little difference. They did, however, report that in one of two years, lambs born to dams who themselves were born from ewe lambs (i.e., the grand-offspring) were slightly heavier at weaning than grand-offspring from mature ewes. If this apparent effect was found to be consistent after weaning, and also to affect carcass characteristics, it might indicate a potential advantage of selecting replacement ewes born to ewe lambs. To date, these relationships have not been examined. Therefore, the present study examined the live weight and carcass characteristics of two cohorts of male lambs born to ewes that themselves were born to either mature ewes or ewe lambs...

BRIEF COMMUNICATION: High milk production in milked sheep grazed in large flocks in New Zealand - McMillan WH; McLachlan SJ; Hercus IS; Lopez-Villalobos N (Proceedings of the New Zealand Society of Animal Production, 2014)
There is a paucity of published information in New Zealand (NZ) sheep on milk production in commercial-scale dairy enterprises. Much of the early research involved small numbers of animals focused on traditional breeds, with the Dorset breed considered the most suitable dairy-type sheep (e.g., Geenty & Jagusch 1974). Importation of East Friesian sheep in the mid-1990s provided new opportunities for sheep dairying (Allison 1996). Since that time, there appears to be a limited number of papers published in NZ on the milking performance of animals of East Friesian origin (e.g., Newman & Steiffel 1999; Peterson et al. 2005)...

BRIEF COMMUNICATION: Inter-generational effects on male offspring born to ewes whose dams were offered varying feeding levels in pregnancy - Burnham DL; Kenyon PR; Pain SJ; Hickson RE; Peterson SW; Blair HT (Proceedings of the New Zealand Society of Animal Production, 2014)
There is a growing body of evidence to indicate that pregnancy nutrition can affect the productive performance of the offspring in sheep (Kenyon & Blair 2014). Recently we demonstrated that pastoral-based feeding of the ewe (G0) can affect the milk production of the ewe offspring (G1) and the growth and live weight of the grand-offspring (G2) to weaning (van der Linden et al. 2009; Paten et al. 2013). An effect of feeding on grand-offspring is termed an inter-generational effect, and while these effects have been reported in species such as mice and rats, their occurrence in the sheep literature is rare. There is some evidence to suggest feeding of the ewe in pregnancy can alter the growth and carcass characteristics of her offspring (see review Greenwood et al. 2010) but there is no data available on potential inter-generational effects. The aim of the present study was to determine if feeding of the ewe (G0) in either early- or mid- to late-pregnancy could alter the live weight and slaughter characteristics of male grand (G2) offspring...

BRIEF COMMUNICATION: Methane emissions by sheep offered high sugar or conventional perennial ryegrass at two allowances - Jonker A; Molano G; Sandoval E; Taylor PS; Antwi C; Cosgrove GP (Proceedings of the New Zealand Society of Animal Production, 2014)
Perennial ryegrass (Lolium perenne L.) with a higher concentration of water-soluble carbohydrates (WSC) has been bred by plant breeders (Humphreys 1989). Ryegrass with a higher WSC can potentially alter rumen microbial fermentation, synchrony of energy and protein in the rumen, total energy supply to the animal and consequently productivity (Edwards et al. 2007). Methane originates mainly from rumen fermentation and is the main greenhouse-gas produced by New Zealand (NZ) agriculture (MfE 2013). The higher concentration of WSC in high sugar ryegrass (HSG) can change rumen fermentation patterns (Lee et al. 2003) and may consequently affect methane emissions. Methane emissions are largely driven by dry matter intake (DMI) (Hammond et al. 2013) and methane mitigation strategies are often more effective at a high DMI (Moe & Tyrrell 1979). However, a true methane mitigation strategy should be effective at any DMI level. The objective of this study was to determine methane emissions from sheep fed freshly cut diploid HSG, conventional diploid ryegrass (CRG) and tetraploid ryegrass (TRG) offered at two levels of metabolisable energy for maintenance (MEm).

BRIEF COMMUNICATION: Milk production, live weight, body condition and somatic cell score during the first 150 days of lactation in Friesian, Jersey and crossbred cows milked once daily - Lambeye F; Lopez-Villalobos N; Burke JL; Davis SR (Proceedings of the New Zealand Society of Animal Production, 2014)
Pasture-based dairy farming in New Zealand has predominately been with cows milked twice a day (TAD). However, since the last decades, milking once a day (OAD) has been adopted by some farmers in New Zealand for herd management and lifestyle benefits (Davis 2005)...

BRIEF COMMUNICATION: Performance of lambs exposed to a desensitising regime prior to infection with Trichostrongylus colubriformis - Greer AW; Huntley JF; Hogan A; Logan CM; McAnulty RW; McNeilly TN (Proceedings of the New Zealand Society of Animal Production, 2014)
Enhancing the immune response of lambs against the gastrointestinal nematode Trichostrongylus colubriformis through vaccination has been previously investigated (Windon et al. 1984; Douch 1989; McClure 2009). However, the majority of production loss from this parasite species in sheep has been attributed to components of the immune response (Greer et al. 2005). As such, manipulation of the host immune response through desensitisation may provide a novel method of reducing production loss associated with infection. The objective of this investigation was to evaluate the ability of a desensitising regime with parasite antigens to reduce the production cost associated with Trichostrongylus colubriformis infection in lambs...

BRIEF COMMUNICATION: Predicting the impact of climate change on the risk of facial eczema outbreaks throughout New Zealand - Dennis NA; Amer PR; Meier S (Proceedings of the New Zealand Society of Animal Production, 2014)
Facial eczema (FE) is caused by the sporidesmin toxin, which is produced by the spores of the fungus, Pithomyces chartarum (PC). Sporidesmin causes damage to the gut, liver and bile ducts in ruminants. This can result in weight loss, decreased production and skin photosensitivity which characterise clinical FE cases (Sheath et al. 1987; Towers & Smith 1978). Production losses also occur in sub-clinical cases, which may go undetected under normal farm management.

BRIEF COMMUNICATION: Quality of meat from steers born to beef-cross-dairy cows and sired by Hereford bulls - Schreurs NM; Hickson RE; Coleman LW; Kenyon PR; Martin NP; Morris ST (Proceedings of the New Zealand Society of Animal Production, 2014)
The dairy industry is playing an increasing role in beef production in New Zealand. It is estimated that 65% of the beef produced in New Zealand originates from dairy herds in the form of Friesian bull beef, first-cross dairy-beef cattle, or cull cows (Morris 2008). The dairy herd has a role in the generation of beef-cross-dairy breed heifers that are used as beef breeding cows. Dairy cattle genetics are not orientated towards meat production and this raises the question as to the suitability of beef-cross-dairy breed cows for producing progeny that are slaughtered for meat production. The quality of meat from the progeny of first-cross dairy-beef cows is largely unknown. The main dairy breed used in New Zealand is the Holstein-Friesian and the Jersey breed is also very predominant. To take advantage of hybrid vigour, the Friesian-Jersey cross is commonplace in the New Zealand dairy herd. The Friesian-Jersey cross is now considered as a breed in itself and called the “Kiwi-cross” or “Kiwi” breed (Garrick & Lopez-Villalobos, 1998). Therefore, the objective of this study was to compare the quality of meat from steers which had an Angus (AA), Angus-cross-Friesian (AF), Angus-cross-Kiwi (AK) or Angus-cross-Jersey (AJ) dam. The steers were sired by Hereford bulls and so, the straight-bred Angus dams (AA) provided steers with beef-only genetics for comparison....

BRIEF COMMUNICATION: Reducing the risk of photosensitisation in dairy cattle undergoing a facial eczema challenge - Cullen NG; Beatson PR; Lee RSF; Dobbie PM; Morris CA (Proceedings of the New Zealand Society of Animal Production, 2014)
Facial eczema (FE) is primarily a liver disease of ruminants that is caused by the ingestion of the toxin sporidesmin which is produced by spores of the fungus, Pithomyces chartarum. The liver and bile-duct injury may be monitored with a non-specific indicator, gamma-glutamyltransferase (GGT; Morris et al. (1990)). Dairy cattle may be assessed for their tolerance/susceptibility to sporidesmin by measuring their GGT activities in blood, about three weeks after a sporidesmin challenge. Under these conditions, logeGGT is heritable (0.34 ± 0.02), according to Cullen et al. (2011)...

BRIEF COMMUNICATION: Relationships between longevity and herd-test traits in a dairy goat herd - Wheeler N; Foote BJ; Foote JF (Proceedings of the New Zealand Society of Animal Production, 2014)
Doe longevity has a significant impact upon the dairy goat industry. Does which maintain good health and high productivity, remaining in the herd for a greater number of years, will reduce the economic and environmental cost of raising replacement breeding animals per unit of milk production. Although longevity has been studied in sheep and dairy cattle (McIntyre et al. 2012, Harris & Montgomerie 2007), there is little information regarding genetic parameters for longevity traits in New Zealand dairy goats. A study (Gautam 2012) has, however, investigated characteristics associated with the length of productive life of dairy goats in New Zealand...

BRIEF COMMUNICATION: Utilising a plantain, red clover and white clover mix - A farmer’s perspective - Brown IC; Morris ST; Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2014)
Cheltenham Downs is located in the Manawatu district of the North Island of New Zealand. The farm was purchased by Landcorp in early 2011. It has a total area of 1427 ha, of which 1237 ha are effective. The farm is primarily utilised as a lamb-finishing enterprise. The property is located in a relatively summer safe area, with a mix of soil types (Rangitikei Sandy Loam and Milton, Te Arakure, Halcombe, Kiwitea, Ohakea, Milson and Manawatu Silt Loams) and has a flat to easy contour. The average rainfall is 1150mm per annum, evenly spread throughout the year. The majority of the farm is in ryegrass-white clover-based pastures. Each year, on average, 100 ha of Hunter brassica and 40 ha of kale are planted. Currently, the farm has 144 ha of the plantain, red clover and white clover mix.

Crossbred cows exceed production expectation in high producing herds - Montgomerie WA (Proceedings of the New Zealand Society of Animal Production, 2014)
New Zealand dairy production per cow has increased by over 33% in the past fifteen years. Consequently, animal breeders are interested in understanding how expression of heterosis for dairy production traits is affected in higher-production systems. To investigate this question a natural-experiment approach was taken, utilising herd-testing records in the 2010-11 dairy production season in herds that contained two breeds, Holstein-Friesian cows ('control' breed) and Holstein-Friesian x Jersey cows ('treatment'). Herds were divided into two production system classes. The system classes were national-average herd production per cow ('control' system) and high per cow production ('treatment'). Per cow yields were over 45% higher in the treatment herds than in national-average herds. Herd test records were analysed for 29,329 two-year-old heifers, and for 20,753 five-or six-year-old mature cows. Dependent variables for the statistical models were deviations from contemporary group means for 270-day yields for production traits. Explanatory variables included Breed, System, and individual cow Production Values as estimated in the national genetic-evaluation system (which include genetic, permanent environment and heterosis effects on yields). In the high-performance production systems the crossbred cows had higher yields than the Holstein-Friesian cows (compared with Production Value predictions) by 5.7 kg milksolids (heifers) and 1.9 kg milksolids (mature cows). This study indicates that heterosis for dairy production traits is more fully expressed in production systems that favour higher per cow yields than in the more restrictive production systems common in the 1990s.

A cross-sectional survey of rider and horse demographics, and the feeding, health and management of Pony Club horses in New Zealand - Fernandes KA; Rogers CW; Gee EK; Bolwell CF; Thomas DG (Proceedings of the New Zealand Society of Animal Production, 2014)
A cross-sectional survey was conducted to describe rider and horse demographics, and the feeding, health, and management of horses and ponies involved with Pony Clubs in New Zealand. An online survey collected information from members of the New Zealand Pony Clubs Association between 1st November 2012 and 31st January 2013. A total of 502 respondents completed the survey. Most riders were female (95%; 455/481) and were ≤16 years of age (74%; 357/481). Decisions on feeding and management of horses were rarely made by the rider alone (26%; 124/476). The rider’s parent or person responsible for the horse were often included in the decision-making, which occurred consistently across all age-groups ≤16 years (P<0.001). Over half (53%; 252/475) of the respondents’ families had more than 20 years of equine experience. On a scale of 1-9, the median body condition score (BCS) of the nominated Pony Club horses was six (interquartile range 5-6), and only 22% (98/446) of respondents indicated that their horse was overweight (BCS ≥7/9). More than 80% of horses were managed on pasture throughout the year, with 24-hour access to grazing each day. In addition to pasture, 82% (409/502) of respondents fed their horses a combination of commercially available equine feeds, including premixed feeds, cereals, and conserved forages. Overall, owners of Pony Club horses reported few health issues associated with their horse.

Dairy industry engagement in the setting and management of water quality limits - Scarsbrook MR (Proceedings of the New Zealand Society of Animal Production, 2014)
The progressive definition of water quality and quantity limits in catchments throughout New Zealand is a positive step towards improving the management of our freshwater resources. The process brings with it significant challenges for the sustainability and competitiveness of the dairy industry. In responding to these challenges, the dairy industry is working to develop a range of systems, resources and capability building programmes that will mitigate risks to the industry and support farmers through what is the largest shift in resource management in a generation. The dairy industry has defined a four-step model for engagement in the process. Essentially, the four steps can be considered to represent the setting of limits to address water quality issues, the definition of regulatory and non-regulatory methods to achieve those limits, managing to limits on farm, and the assessment of progress towards desired outcomes

Design and implementation of the Deer Progeny Test (DPT) - Ward JF; Archer JA; Asher GW; Everett-Hincks JM; Mathias-Davis HC (Proceedings of the New Zealand Society of Animal Production, 2014)

Evaluating new forage systems for East Coast dryland - Macfarlane MJ; Thomson BC; Crofoot E; Hamilton G; Ashby H; Muir PD (Proceedings of the New Zealand Society of Animal Production, 2014)
Dry matter production and animal performance on plantain and erect annual clovers were monitored on four demonstration sites from 2012 to 2014. These studies confirmed plantain’s potential for increasing both the quantity and quality of forage produced on cultivated and un-cultivatable hill country. Newly sown plantain produced more dry matter than newly-sown ryegrass over winter and spring. Across three sites, plantain pastures had more clover (32%, 45% and 45%) in October. Lambs grew faster on plantain and had higher dressing-out percentages. Plantain appears less competitive than ryegrass and the grazing management it requires suits erect annual clovers (e.g. Balansa, Persian, Arrowleaf). Because these clovers are aerial seeders, achieving seed set is challenging under grazing. Until management systems can be developed to allow seed set, these clovers are destined to be an annual crop producing a bulk of high quality spring feed in suitable micro-climates. Plantain and erect annual clovers offer a promising alternative to ryegrass-based systems on dryland. However, there is much to learn about the best place for each species and how they fit within a farm system. As with lucerne, plantain and erect annual clovers need to be rotationally grazed to prevent damage to the crown and growing points. The success of these alternative forages in dryland will depend on farmer willingness to embrace new grazing management techniques.

The Farmer Learning Project: Improving the design of agricultural extension to promote learning - Sewell AM; Blair HT; Grey DI; Hartnett M; Kemp PD; Kenyon PR; Morris ST; Wood BA (Proceedings of the New Zealand Society of Animal Production, 2014)
New Zealand has played a key role in developing innovative extension models designed to support farmers to adopt new, evidence-based, farming practices. However, this momentum has been lost over recent years. A fresh and innovative model of extension is needed to ensure that New Zealand farmers learn about highly-effective technologies. The Farmer Learning Project, now in its third year, is a multi-disciplinary research venture that aims to find out how to promote farmers’ learning and adoption of evidence-based practices. This paper provides an overview of the Farmer Learning Project at Massey University and its innovations designed to promote learning about herb-mix pastures containing chicory, plantain and red and white clover. Five critical success factors shown to support the farmers’ learning are discussed. These include the importance of participation in a sustained and inquiry-focused farmer-scientist learning community, and their engagement in a variety of repeated and relevant learning experiences that are aligned to science. Underpinning these success factors are seven educational principles that need to inform design innovations in agricultural extension. Early findings are also shared from the second phase of the project, which investigates the farmers’ practice change as a result of their learning about herb pastures and its ability to create high performance sheep grazing systems.

Farmer learning, successful technology transfer and agricultural extension - Kenyon PR; Morris ST; Corner-Thomas RA (Proceedings of the New Zealand Society of Animal Production, 2014)
Agriculture has played and will continue to play an important role in the New Zealand economy. New Zealand earns $30 billion a year from its primary industries, which make up over 70% of New Zealand’s merchandise export earnings (Ministry for Primary Industries 2013). The primary sector as a whole had a 3.3% annual compound growth rate during the period 1984 to 2007, while forestry was at 1.6% and the wider economy at just 1.0% (Morris 2013). Further, productivity of the primary industries has increased 2.5 times from 1978 to 2009, almost twice as much as the wider domestic economy (Ministry for Primary Industries 2013)...

Farming within limits – can system fundamentals be the key? - Beukes PC; Romera AJ; Clark DA (Proceedings of the New Zealand Society of Animal Production, 2014)
The design of dairy systems with increased production and profit, but reduced environmental footprint, presents a problem with objectives that are seemingly at odds. We argue that this is why we have to go back to the ecological principles that underpin farm systems and use these to develop new systems that will achieve the above objectives. Healthy topsoil is a living nutrient trap. It requires long term thinking and action to achieve and maintain healthy topsoil. The rumen is a very complex ecosystem with the microbes as a key component. Farm systems aimed at optimal performance per cow, with lowest possible methane and urinary nitrogen waste products consistent with this performance, need to ensure effective rumen function. Maintenance dilution and cow longevity are important principles for sustainable and profitable farming. Pastoral livestock systems need ecological and financial buffers to remain resilient in uncertain times. We present a plan consisting of five strategies, based on some of these fundamentals, that we believe is a step towards farming profitably and within limits.

Farming within limits; the new reality. Concluding remarks - van Reenen EH (Proceedings of the New Zealand Society of Animal Production, 2014)
In 2002, Fish and Game New Zealand launched arguably one of the most successful environmental campaigns since the anti-nuclear movement which began in the 1950s. The ‘Dirty Dairying Campaign’ set the agricultural sector on a path to addressing its impact on the environment in a much more public and open forum than had been seen before. Within a generation, farmers have gone from receiving government funded incentives to increased stocking rates, cleared bush and scrub, and applied what we now know to be excessive amounts of fertiliser. They are now faced with the prospect of farming within limits imposed either naturally or by regulation.

Farming within limits; the new reality. Introductory remarks - van Reenen EH (Proceedings of the New Zealand Society of Animal Production, 2014)
The National Policy Statement for Freshwater Management establishes a range of policies directing local government to manage water sustainably in an integrated manner. A key purpose of the statement is to set enforceable quality and quantity limits that reflect local and national values allowing for economic growth to occur (Ministry for the Environment 2011). Limitations on resources will be the new reality for farmers, as is now the case in the Taupo and Rotorua catchments. This Contract Session will discuss the role of ‘system fundamentals’ in profitably farming within limits, the dairy industry response to improving the management of freshwater resources, a recent collaborative example of producing a mitigation resource for farmers, and the needs of resource constrained farmers from scientists in the next 20 years.

From Extension to Distributed Learning: The Embedding of Agricultural Scientists in Farmer Knowledge Networks - Wood BA; Blair HT; Grey DI; Hartnett M; Kemp PD; Kenyon PR; Morris ST; Sewell AM (Proceedings of the New Zealand Society of Animal Production, 2014)
This paper reports on the social structures of an ongoing learning group in which 17 farmers and five agricultural scientists are collaboratively undertaking a three-year farmlet experiment that investigates the performance of ‘herb mix’ pastures. Network analyses have been undertaken of the history of prior contact between the group’s 22 members and of the 223 contacts made by the participating farmers to develop their herb pasture knowledge. The results show that networking by farmer members radically increases the ability of science to reach other farmers. These farmer networks have distributed structures characterised by dense, decentralised and equitable ties between the participants. The power to authorise agricultural knowledge is pluralised by numerous self-reinforcing relationships grounded in everyday farming practices. The paper concludes by discussing the relevance of such distributed learning for current attempts to replace linear extension with a more productive approach to agricultural knowledge.

Grazing behaviour, dry matter intake and urination patterns of dairy cows offered kale or fodder beet in winter - Jenkinson BAB; Edwards GR; Bryant RH (Proceedings of the New Zealand Society of Animal Production, 2014)
The opportunity to reduce nitrogen (N) losses to the environment from wintering systems for dairy cows may arise from a combination of restricted grazing systems and feeding low N diets to reduce N intake. Lack of information on urination behaviour and grazing intake during restricted grazing makes it difficult to predict animal and environmental responses. Three winter forage systems were simulated and pregnant, non-lactating Friesian x Jersey dairy cows were offered diets which varied in crop allowance and supplement: early sown-kale (EK) comprising 14 and 3 kg DM/cow/d of kale and barley straw; late-sown kale (LK) comprising 11 and 5 kg DM/cow/d of kale and green-chop oat silage; and fodder beet (FB) comprising 8 and 6 kg DM/cow/d fodder beet and grass baleage. Grazing behaviour, DM intake, DM utilisation and urination and faecal frequency, were recorded for six hours following morning crop allocation. After six hours, utilisation of EK, LK and FB crops were 82, 76 and 90%, corresponding to respective DM intake rates of 1.9, 1.4 and 1.2 kg DM/cow/hr. Average urination frequency (2.7 urinations/cow) and duration (9.1 seconds/urination) during the six hour grazing bout was similar for all treatments, and urine N concentration was also similar for each treatment (2.22 g N/L). As cows consumed a high proportion (> 75%) of their daily intake within six hours, and few urination events occurred during this period, the results indicate suitability for use of these systems in a restricted grazing regime combined with a standoff pad in order to mitigate losses of N to environment.

Growth rates of dairy heifers fed alternative feeds - de Clifford RP; Hickson RE; Martin NP; Back PJ (Proceedings of the New Zealand Society of Animal Production, 2014)
Dairy heifers need to achieve average daily gains (ADG) that allow them to reach liveweight targets. The aim of this experiment was to measure the effects of grazing 6-month-old dairy heifers on alternative feeds, over the summer period. Sixty 6-month-old Friesian-Jersey crossbred heifers were assigned to one of three treatments (pasture (P), conserved forages (C) or lucerne (L), with all treatments receiving supplementary meal. For the 6-week experiment, feed allowance was based on liveweight gain required to meet liveweight targets. Heifers were weighed at 0, 3 and 6 weeks of the treatment period. Wither height, crown-to-rump length and girth circumference were measured at the start and end of the experiment. L heifers had a greater (P<0.05) average daily gain (1.22 + 0.03 kg/day) than P heifers (0.57 + 0.03 kg/day), and C heifers were intermediate (0.78 + 0.03 kg/day). L and C heifers had a greater (P<0.01) increase in wither height (0.15 + 0.01 cm/day and 0.14 + 0.01 cm/day respectively) than P heifers (0.11 + 0.01 cm/day). L heifers had the greatest (P<0.05) increase in girth circumference (0.30 + 0.02 cm/day, compared with P and C heifers: 0.22 + 0.02 cm/day and 0.16 + 0.02 cm/day respectively). A combined diet of lucerne and meal during drought conditions increased ADG resulting in a greater proportion of heifers reaching liveweight targets.

Induction of delayed-type hypersensitivity reactions to Candida albicans in pasture-based dairy cows - McGowan JE; Hine BC; Mallard BA; Verkerk GA (Proceedings of the New Zealand Society of Animal Production, 2014)
Delayed-type hypersensitivity (DTH) reactions to Candida albicans are regularly used as an in-vivo indicator of cell-mediated immune function in cattle. Prior immunisation against C. albicans ensures a large clone of antigen-specific memory T cells, resulting in larger DTH responses and positive responses from a greater proportion of cows. Previous experimental results indicate that natural exposure to C. albicans is minimal in cows housed indoors and does not interfere with the interpretation of DTH responses to C. albicans in pre-immunised cows. However, housed cows may have different natural exposure to C. albicans than cows grazing fresh pasture outdoors. To determine if C. albicans is an appropriate antigen for inducing measurable DTH responses in pasture-based cows, DTH responses to C. albicans were assessed in ten cows pre- immunised with C. albicans and ten unimmunised control cows. A greater proportion of immunised versus unimmunised cows mounted a positive DTH response (90% vs. 70%), and responses were larger (P<0.01) and more variable (P<0.05) in immunised cows. Maximum relative double skinfold thickness increased 4.3 mm (±0.7; SEM) and 1.4mm (±0.2) in immunised and unimmunised cows, respectively. The results of this experiment suggest that pasture-based dairy cows in New Zealand have a low background exposure to C. albicans and pre-immunisation with C. albicans is required when using DTH responses as an indicator of cell-mediated immune function in pasture-based cows.

Is it time for changes in the New Zealand Society of Animal Production? - Kenyon PR (Proceedings of the New Zealand Society of Animal Production, 2014)
At approximately ten year intervals, the President’s address includes a review of society’s activities (Andrews 1963; Everitt 1973; Smith 1984; Nicol 1992; Morrow 2004). Therefore, it is appropriate that I do so again. In addition, the society is facing the reality of falling paper numbers and attendance at conferences. Coinciding with this is a change in the generation of active scientific members within the society. Therefore, my address will also outline my thoughts on these issues moving forward.

Matching need with delivery: New Zealand farmer learning case studies - Dynes RA; Brown MA; Bewsell D (Proceedings of the New Zealand Society of Animal Production, 2014)
Effective farmer extension programs are needed for industry to capture the benefits of agricultural research. We describe three case studies adopting different delivery approaches to extension. Each case study was developed using key principles of adult learning, particularly the principle of learner-centred approaches where farmers are part of the design and development of workshops, tools and resources. The case studies are discussed in relation to the needs of the adult learner, including the need to know, self-concept, prior experience, readiness to learn, learning orientation and motivation to learn.

Menus of practice to improve water quality – a Waikato example of collaboration in action - Abercrombie R (Proceedings of the New Zealand Society of Animal Production, 2014)
Water quality in the Waikato Region is highly variable, despite ongoing efforts from farmers, iwi, industry, local government and other stakeholders in the region. Intensive farming is a major contributor to areas of poor water quality. Levels of nitrogen in the region’s waterways have been rising slowly but steadily over the last 20 years. Nitrogen in groundwater can take decades to emerge into surface water. Hence, this indicator of water quality will worsen before it improves. Levels of micro-organisms are moderate to high, but stable. Sediment levels are high in places, and phosphorus levels vary. Menus of good practice to improve water quality arose from direct requests by farmers and have been developed by collaborative effort between the Waikato Regional Council, research and industry bodies. They provide farmers and consultants with a decision support tool that is both scientifically rigorous, and flexible enough to meet the needs of individual farmers’ circumstances by providing an objective assessment of the relative benefits of a range of practices for their mitigation of nitrogen, phosphorus, sediment and bacterial discharges from farms. The procedures can also be used as a contribution to the review of the current Regional Plan.

Plants for dairy grazing systems operating under nitrate leaching limits - Chapman DF; Edwards GR; Pinxterhuis JB (Proceedings of the New Zealand Society of Animal Production, 2014)
Regulations that place a limit on the amount of nitrate-nitrogen leaching from agricultural land are currently being developed by Regional Councils throughout New Zealand. These regulations may require substantial reductions in nitrate leaching from current typical dairy farm levels. Notions of the pasture plant ‘ideotype’, which have previously emphasised pasture growth and the intake of digestible nutrients, should now also include characteristics which can reduce the nitrogen surplus in the animal, and, therefore, the amount of nitrogen (N) excreted in urine. Information on the critical external or internal N requirements of candidate pasture species could be used to develop hypotheses regarding future grazed forage systems; currently, there are few data available for this purpose. Recent empirical evidence indicates that diverse pastures incorporating forage herbs such as chicory and plantain can reduce total urinary N load while maintaining similar levels of herbage accumulation to ryegrass-white clover pasture. However, insufficient information is available to identify the mechanisms through which the urinary N reductions occur. This specific knowledge gap needs to be filled. In addition, more information is needed on the general nitrogen nutrition physiology of candidate pasture species for future forage systems.

Practical implications of theoretical modelling of in-line milk meters - Dowson O; Anderson G; Hempstalk K (Proceedings of the New Zealand Society of Animal Production, 2014)
In-line milk meters are devices which measure the milk yield of dairy cows at every milking; however, they are also susceptible to error. This results in frequent, but inaccurate, measurements. This paper attempts to model a lactation curve and accumulated milk yields from these devices. Wood’s model of a lactation curve was used to predict milk yield. This was modified by adding both systemic and random daily variation. The meters were modelled by taking the modified Wood’s lactation curve for each cow and altering it with various error terms. Along with precision, each sensor also had a rate of drift, and a rate at which its variance grew. It was found that the precision of a sensor can be low, however by aggregating multiple records it is possible to obtain an accurate value for total yield. One strategy that improved the total yield accuracy was to scale the measurements obtained for a particular sensor in a given milking. Due to the uncertainty surrounding the errors involved, and the large assumptions that were made, this model is a good starting point for future work. It is able to identify the relative effect of errors on meter accuracy, and test strategies to improve accuracy of daily and total milk yield.

Predicting fleece weight from the difference in live weight pre- and post-shearing - Galway JM; Logan CM; Bywater AC; Greer AW (Proceedings of the New Zealand Society of Animal Production, 2014)
Radio frequency identification (RFID) and automated weighing platforms facilitate the practicality and ease with which individual live weight (LW) can be recorded. This raises the possibility for the difference in recorded LW of sheep between pre- and post-shearing to provide an estimate of fleece weight (eFW) which, in turn, could allow selection pressure to be applied for improved wool production. The eFW of yearling ewes (n=98), yearling rams (n=274) and mixed-age ewes (n=305) were compared with their recorded fleece weight (FW). Positive linear correlations (P<0.001 for all stock classes) were observed between eFW and FW and also the eFW rank and FW rank. Although some variability between stock classes existed, for all data combined, FW rank was able to account for 42% of the variation in eFW rank. Further, selecting individuals on eFW was able to retain an average of 64% of the selection differential obtained using recorded FW. Overall, these results suggest eFW calculated from the difference in LW between pre- and post-shearing, in combination with RFID and automated weighing platforms, may provide a useful and practical tool to assist with selection for improved wool production in a commercial setting.

Preference for different pasture grasses by horses in New Zealand - Randall L; Rogers CW; Hoskin SO; Swainson NM (Proceedings of the New Zealand Society of Animal Production, 2014)
In New Zealand, grazed pasture is the primary nutrient source for equines, but little is known about equine grass preferences. A study to identify preferred grass species and/or cultivars (here on referred to as grasses) by horses was conducted in a 0.62 ha paddock containing 22 different test grasses. The grasses tested were planted in 6 x 3 m plots with four replicates of each species/cultivar. Four mature mares 527± 38 kg, mean age 9 ± 3 years, were grazed on the trial plots for a total of five days during May 2007. Grass preference was quantified by; direct DM utilisation (pre- vs post-grazing dry matter cuts), pasture-probe measurement and visual assessment through photographs. Grass preference was similar for each method used to quantify utilisation (r2=0.73 – 0.76 P<0.0001). The six grasses most preferred by horses were all tetraploid ryegrasses (DM utilisation 74% (inter quartile range 67-81%). Least-preferred grasses were Yorkshire fog and Cocksfoot (DM utilisation down -0.9 to -14%). Hot water soluble carbohydrate and digestible organic matter in the dry matterwere the best predictors of grass preference. There was no significant effect of endophyte status (High, AR1, and Nil) on pasture preference during late autumn.

Prevalence and risk factors for respiratory disease on Thorougbred and Standardbred stud farms in New Zealand - Rosanowski SM; Cogger N; Rogers CW; Bolwell CF (Proceedings of the New Zealand Society of Animal Production, 2014)
Respiratory disease has been identified as an important and production-limiting health problem on equine stud farms. This study aimed to describe the prevalence and risk factors for respiratory disease on commercial Thoroughbred and Standardbred stud farms in New Zealand, using logistic regression analysis. In 2012, 33 stud managers were interviewed regarding the 2010/11 and 2011/12 breeding seasons, including stud manager reported respiratory disease and strangles vaccination practices. Twenty-two stud mangers reported having respiratory disease on their stud farm in the 2010/11 breeding season, and twenty-six stud managers reported disease in the following season. On 90% of stud farms, nasal discharge was reported by stud managers as the main sign of disease and on 41% of stud farms no treatment was undertaken. When breeding season and the size of the stud farm were accounted for, vaccinating horses against strangles increased the odds of horses having experienced respiratory disease (OR 7.26, 95% CI 1.48-35.64), while the presence of a stallion decreased the odds (OR 0.05, 95% CI 0.004 - 0.48). This study has confirmed that respiratory disease is a common health issue on Thoroughbred and Standardbred stud farms in New Zealand.

Ramguard – Increasing the Tolerance to Facial Eczema in New Zealand Sheep - Amyes NC; Hawkes AD (Proceedings of the New Zealand Society of Animal Production, 2014)
Facial eczema (FE) is a metabolic disease resulting primarily from damage to the liver and bile ducts. It is caused in ruminants by the effects of a mycotoxin, sporidesmin, produced by the fungus Pithomyces chartarum. The disease causes significant loss in agricultural production mainly in northern New Zealand. Sporidesmin toxin is produced in a laboratory and made available to those sheep breeders who wish to increase the level of FE tolerance in their flocks. The sheep industry in NZ has made steady progress towards increasing genetic tolerance to FE by testing potential future sires in ram-breeding flocks with an artificial challenge of sporidesmin. Ramguard provides the sporidesmin to breeders to dose their sheep at a specified dose-rate which is dependent on the level of tolerance already obtained. The Ramguard service has operated from August 1988 and has 60 clients dosing a total of 800 to 1100 rams each year. Most of the long-term-testing flocks are now using a dose rate six times higher than at the outset, which indicates animals in these flocks are tolerant to all but the severest outbreaks of FE. The heritability estimate for resistance to facial eczema is high at 0.45 ± 0.03.

A review of recent research and extension on dryland lucerne in New Zealand - Moot DJ (Proceedings of the New Zealand Society of Animal Production, 2014)
To maintain scientific integrity requires the publication of research articles in journals of high international standing. Results from such work are frequently discounted as irrelevant and of low value to practitioners wanting to interpret results for their farm situation. This creates a dilemma for funding bodies, scientists and industry good organizations. This paper outlines the strategy that has evolved to develop a dryland research programme based around lucerne. This aimed to satisfy the requirements of data integrity for excellent science output, yet maintain currency and relevance for wide-spread agricultural adoption. This utilized high quality science by a series of postgraduate students, and engaged industry good and Government organizations to provide funding support to demonstrate the key results, and for technology transfer. The successful adoption of information required the lead scientist to engage in all aspects of the science and extension. As the demands of each increased, digital technology in the form of a website, ‘txt’ alert service, and a blog were used to communicate to a wider audience and maintain accurate and timely advice. The development of a case study around ‘Bonavaree’ farm provided a focus for on-farm adoption and added currency and relevance to the scientific data. This allowed scientists, agribusiness professionals and on-farm practitioners to communicate with a farmer or scientist at a level that they felt most comfortable. The collective result has stimulated on-farm change to a greater extent than could be expected from a focus on any individual component of research, demonstration or technology transfer.

Rumen Microbial Community Profiling as a Tool to Study Ruminant Production - Janssen PH; Kittelmann S; Henderson G; Seedorf H (Proceedings of the New Zealand Society of Animal Production, 2014)
The species composition of the rumen microbial community is shaped by the ruminant host and by characteristics of the ingested feed. The microbes present determine the ratios of volatile fatty acids, gases such as methane, and microbial protein formed from the feed. The rate of feed fermentation and the mix of products are important for animal production and for environmental impacts of ruminant farming. Differences in microbial community composition within a cohort of animals on a specific feed indicate differences in the rumen environment and presumably host animal genetics or early life history. Differences in the community when animals are on different feeds can be used to understand the impact of the feed on rumen function. Interpreting these community differences relies on understanding what might cause the selection of one community type over another. Recent research in New Zealand has developed a pipeline for studying rumen microbial community compositions. These tools have been used to help understand the basis of lower methane emissions from sheep fed forage brassica compared to ryegrass, and to understand what drives natural variations in methane emissions from sheep. This type of analysis is also starting to be used to investigate productivity differences within animal cohorts.

Ruminant response to non-live probiotic microorganism extracts - Jenkins TA; Jenkins V (Proceedings of the New Zealand Society of Animal Production, 2014)
Live probiotic microorganisms can improve ruminant productivity but results are variable and modes of action uncertain. Non-live microbial extracts provide insight into probiotic modes of action and their efficacy challenges the definition of probiotics. Twenty-two trials on lambs and ten on dairy cows were undertaken with non-live probiotic microorganism extract products RumenZyme Plus (RZP) and ProDairy (PD) respectively. Lambs treated with single or double doses of RZP tended to gain extra live weight relative to control with a 445 g median treatment response (P=0.001). The patterns of RZP results did not fit with an anti-inflammatory response alone but rather general productivity improvement. Cows receiving daily doses of PD had higher daily MS production with mean treatment response of 49.7 g/cow/day (P=0.008, 95% confidence interval of 16.3 to 83.2 g/cow/day). There was no evidence of benefit from the addition of live probiotic lactic acid bacteria in these trials. Live lactic acid bacteria supplementation actually reduced response relative to the non-live probiotic extract in one dairy and two lamb trials (P<0.05). The results in this study demonstrated efficacy of non-live probiotic extracts for ruminant productivity.

Sheep Dairying in New Zealand - The Kingsmeade Story - King ME; King JE; Powell CB (Proceedings of the New Zealand Society of Animal Production, 2014)
Kingsmeade has been at the forefront of sheep dairying and innovative cheese-making practises in New Zealand since its inception in 1996. Breeding East Friesian sheep for temperament, type, and productivity has resulted in ewes, including hoggets, capable of achieving lactation lengths in excess of 250 days. A purpose-built factory on their 11-hectare Wairarapa farm currently produces 8.5 tonnes of sheep cheese annually. A further 8.5 tonnes of cow cheese is also produced on-site. Sustainable business practises have been created to ensure minimal wastage and environmental damage. Sales of cheese occur predominantly in the North Island and have been focused on long-term customer relationships by supplying smaller, more exclusive retailers and wholesalers with a unique, artisan product. Further expansion is dependent on acquiring local sheep milk producers. Export is planned with increased cheese production.

The sire breeding programmes of the Department of Lands and Survey and Landcorp Farming Limited - Nicoll GB (Proceedings of the New Zealand Society of Animal Production, 2014)
Over 44 years to 2011, the Department of Lands and Survey (Lands and Survey) and its successor Landcorp Farming Ltd (Landcorp), operated sire breeding programmes to service the large populations of females run on the many commercial farms operating under these two respective institutions. Following the establishment of the first breeding programme in 1967 (the Waihora Romney Programme), a total of 19 sheep, six beef cattle, 15 deer, and four goat programmes were established at one time or another. When Landcorp was formed in 1987, the breeding programmes were regarded as an integral part of a new coordinated production system. Breeding programmes that promised a better commercial fit for Landcorp replaced older programmes that did not. By 2011, there were five sheep, four beef cattle and five deer herds involved as either maternal- or terminal-sire breeding programmes, all of which have shown positive rates of genetic improvement and sire rankings that are at the forefront of their respective breeding industry sires. As the first animal breeding scientist appointed by the Department of Lands and Survey in 1982, it has been a privilege to have technically managed the breeding programmes, and the development of new selection criteria, database facilities and measurement techniques. This “legend” of the Lands and Survey and Landcorp breeding programmes is a documentation of an internationally unique large-animal breeding resource.