@article {3672,
	title = {Grazing behaviour of young cattle around faecal pats},
	journal = {New Zealand Journal of Animal Science and Production},
	volume = {81},
	year = {2021},
	month = {01/2022},
	pages = {63-67},
	address = {Online},
	abstract = {Young Holstein Friesian bulls grazed four mixed-contour paddocks for a duration of three days on ten occasions between December 2002 and March 2004. For the first seven grazing events, five faecal pats on both easy- (<25o) and steep-contoured land in each paddock were selected for monitoring herbage removal during the subsequent four to five grazing events. After each day of grazing, pasture height was measured at 5-cm intervals for 50 cm from the centre of each pat. The decrease in pasture height was converted to estimates of herbage dry matter removal. For the first three grazing events following pat deposition, avoidance of grazing herbage around pats was greatest on the first day of the three-day grazing duration. The mean distance of grazing from the centre of the pats was 21, 14, 10 and 7 cm for the first to fourth grazing events following deposition. Avoidance was greatest around pats that were deposited in late spring/early summer with little difference occurring between pats located on easy or steep land. Increased grazing pressure appeared to override the natural behaviour of young cattle to avoid grazing close to faecal pats. Grazing management of young cattle should ensure residuals of at least 1500 kg DM/ha in order to minimise the grazing of herbage surrounding faecal-pat areas which are highly contaminated with parasite larvae.
Keywords: cattle; grazing behaviour; faecal pats; cattle parasites},
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW and Burggraaf VT}
}
@conference {41516,
	title = {The effect of weaning date, gastro-intestinal nematode challenge and nutrition on beef calf growth},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {64},
	year = {2004},
	month = {Jan},
	pages = {257-261},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {Two experiments were conducted to understand the interactions between calf weaning date, level of nutrition and parasite challenge. In the first experiment, spring-born calves were weaned at 6 or 9 months of age (early or late weaning) and subject to natural parasite challenge, or natural plus an additional dose of 7500 infective larvae/day. Late weaned calves (with cows) also had either high or low pasture allowance treatments imposed. When calves were 9 months of age, calf liveweights (kg) were 253, 302 and 277 (SED 3.9) for the early wean/high nutrition, late wean/high nutrition and late wean/low nutrition treatments respectively and high and low nutrition cow liveweights were 494 and 479 kg (SED 4.8) respectively. At 9 months of age, early weaned calves showed higher faecal egg counts (P<0.05). Dosing with additional parasitic larvae had no effect on early weaned calves, but lowered late weaned calf weights. In the second experiment, calves were weaned at 6 months of age or left un-weaned until the age of 9 months when all calves were slaughtered. Un-weaned calves showed lower gastro-intestinal worm counts than early weaned calves. In both experiments, late weaned calves showed substantial liveweight advantage and lower parasite burdens. Reducing the nutrition of late weaned calves and cows reduced the size of this liveweight benefit. Later weaning is a management option for farmers seeking to reduce reliance on anthelmintic drenches without the associated production loss. },
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW and Vlassoff A}
}
@conference {41406,
	title = {Interaction of gastro-intestinal nematodes and calf weaning management on beef cattle growth},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {63},
	year = {2003},
	month = {Jan},
	pages = {61-65},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Queenstown},
	abstract = {An experiment was undertaken to study the effects of calf weaning management on growth rates and susceptibility to gastro-intestinal nematodes. Treatments were: weaned at 6 months (of age) and normal anthelmintic use; weaned at 6 months and no anthelmintics; weaned at 6 months yet grazed with dam until 9 months and no anthelmintics; weaned at 9 months and no anthelmintics. At 9 months of age, calf live weights for the four treatments were: 264, 253, 265 and 308 kg respectively (SED = 2.0). Faecal-egg counts and serum pepsinogen levels were not affected by weaning date. Milk consumption by the later weaned calves was 4.2 kg/day, resulting in herbage intakes being 25\% lower than calves in other treatments (P<0.01). When suckling calves to 9 months of age, the cost of this milk production to the cow was 26 kg live weight (SED = 6.3). Later weaning gave a substantial increase in calf live weight (P<0.001), which can be attributed to milk consumption. Faecal-egg counts and serum pepsinogen levels indicated that milk consumption did not have a direct effect on gastro-intestinal nematode burdens. },
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW and Vlassoff A}
}
@conference {41182,
	title = {Winter grazing management effects on beef finishing system performance},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {60},
	year = {2000},
	month = {Jan},
	pages = {139-142},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {A beef farm systems experiment was conducted for 2 years in which winter grazing management of either a fast rotation (FR) of 45 days, or a slow rotation (SR) of 120 days was applied to eight small farms containing either rising-1yr, or rising-2yr Angus steers (15/farm). All farms were managed in a fast rotation (<35 days) during spring and summer.Average farm pasture covers at the end of winter were 563 ({\textpm}80) and 347 ({\textpm}53) kg DM/ha higher on the SR farms than the FR farms for the first and second years respectively. The FR steers at the end of winter were on average 26 ({\textpm}4.0) and 22 ({\textpm}4.2) kg heavier than the SR steers in the first and second years respectively. By late summer, the FR steers were 15 ({\textpm}5.3) kg heavier and 2 ({\textpm}5.6) kg lighter than the SR steers. There were no significant management interactions with age class. Live weight compensation of the SR steers was rapid during the first 6 weeks of spring. The results of this experiment show that winter grazing rotation length had little effect on the final live weight achieved by summer. However, between year differences showed that systems compensation during spring is dependent on pasture supply, pasture quality and stocking rate. With the ability of a whole-farm system to show compensation, a slow winter rotation is a low risk option if climatic uncertainty is an issue. },
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW}
}
@conference {41084,
	title = {The results and success factors of nine group farm monitoring programmes},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {59},
	year = {1999},
	month = {Jan},
	pages = {87-90},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Results from 9 farmer groups located in the upper North Island and operating over the period of 1988 to 1998 showed that group farm monitoring has facilitated changes in farm practice performance and income.  The process in-volved groups of farmers with associated consultants, veterinarians and scientists; and the detailed monitoring of a central farm for 3 to 4 years.  Changes made on the monitor farm incorporated the optimisation of the farm system and the adaptation and use of new sheep and beef cattle farming technologies.  Increases in production ranged from 8 to 37\%; and increases in farm revenue from 13 to 31\%.  Changes to stock policies that better aligned feed demand and supply, in-creased growth rates of young animals and greater efficiencies in breeding ewe and cow performance were common contributors to improved performances.  The group farm monitoring process emphasised the value of gathering and effectively using farm and product information and provided a collective learning environment for farmers within a group context.  Critical success factors that have emerged from a decade of work experience associated with group process are highlighted and discussed in the paper.},
	issn = {1176-5283},
	author = {Sheath GW and Webby RW and Keeling P and Thomson RD and Page CR and Burton GT}
}
@conference {41109,
	title = {Tactical supplementation of beef finishing cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {59},
	year = {1999},
	month = {Jan},
	pages = {162-167},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The impact of high quality supplementary feeds on cattle growth rates was investigated in 2 experiments. The first experiment was conducted during late summer (8 weeks) and involved 5 treatments which were replicated twice: no supplement, 2 and 4 kg rolled maize grain/hd/d; and 2.3 and 4.6 kg DM/hd/d high quality pasture silage. The second experiment was conducted during late winter (8 weeks) and involved 3 treatments which were replicated twice: 0, 2 and 4 kg/hd/d rolled maize grain. Rising 2 year steers were used and all pre- and post-grazing pasture masses were similar between treatments within each experiment. During the summer experiment pasture quality was poor and steer liveweight gains for the 5 treatments were: -0.04, 0.44, 0.55, 0.29 and 0.36 kg/hd/d respectively. In contrast, pasture quality was high during the winter experiment and liveweight gains were: 0.93, 1.09 and 1.25 kg/hd/d respectively. The combined results of this experimental series show a consistent liveweight gain response to supplementation of high quality feeds, under both low and high quality pasture conditions. A general response of 0.15-0.20 kg liveweight gain/kg DM grain can be expected. Given current grain prices in New Zealand, its use as a tactical supplement in beef finishing systems will be confined to overcoming variable forage supply and attaining supply contract premiums. Pasture silage is an alternative supplement for summer, but high quality is a pre-requisite. },
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW}
}
@conference {41039,
	title = {Grain supplementation of finishing beef cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {58},
	year = {1998},
	month = {Jan},
	pages = {239-242},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Low pasture quality in summer-autumn and feed deficits during winter are major constraints to achieving consistently high growth rates in beef cattle finishing systems. Two experiments were run to investigate the tactical use of grain supplementation as a tool to overcome performance constraints during these seasons. The first experiment was conducted during January-March (8 weeks) and involved 4 supplementation treatments: 0, 2, 4, and 6 kg grain supplement/hd/d. The second experiment was conducted during July-August (8 weeks) and also involved 4 supplementation treatments: 0, 1, 2, and 4 kg/hd/d. Rising 2 year steers were used in these experiments and pre- and post-grazing herbage masses were similar for all treatments within each experiment. During the summer experiment, steer liveweight gains were 0.05, 0.43, 0.65 and 0.80 kg/hd/d for the 4 supplementation levels respectively. During the winter experiment, average liveweight gains were 0.89, 1.08, 1.30 and 1.35 kg/hd/d. After grain supplementation ceased, liveweight advantages were eroded by compensatory gain occurring in the lower supplementation treatments. The average liveweight response to grain was similar in both experiments (0.18 kg liveweight gain/kg DM supplement), but was highest and most consistent at the 2 kg/hd/d supplementation rate. Acidosis was evident in 1 replicate of the highest supplementation treatment in each experiment. The use of a grain supplement can give reliable weight gain responses and could be valuable as a tactical tool to ensure that time and market bound supply contracts are fulfilled during difficult seasons. The use of this practice in systems that supply to commodity markets is unlikely to be economic. },
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW}
}
@conference {40960,
	title = {Nutritional effects on Beta-carotene concentrations in the fat of beef cattle.},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {57},
	year = {1997},
	month = {Jan},
	pages = {282-285},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Yellow fat reduces the acceptability and value of beef table cuts within the high priced Asian markets. The concentration of carotenoids in fat, leads to this yellowness. A systems experiment which ran for 2 years, studied the effects of nutrition and age on fat carotenoid concentration (FCC). In each year, rising 1-year (R1) and 2-year (R2) Angus steers were offered either full access to winter and spring feed (fast rotation, FR); or were nutritionally restricted during winter (slow rotation, SR) and then given full access to feed during spring. Fat biopsy samples were collected every 4 months and carotenoid concentration determined. FCC increased as animals became older. The effect of the nutritional growth path was to increase FCC during winter where feeding was restricted, particularly in the R1 steers. In both years, the SR systems compensated during spring, with both live weight and FCC being similar for the 2 nutrition treatments by the end of spring. From a practical perspective, farmers who seek to supply beef with satisfactory fat colour should not restrict feeding during the period of 3-4 months prior to slaughter. The experiment also provided data which allowed FCC to be followed from weaning through to slaughter for individual animals. These data provided the opportunity to investigate the prediction of carcass FCC based on earlier fat measurements. Correlations (r) ranged from 0.31 at 24 months to 0.71 at 3 months before slaughter. Correlations are not sufficiently strong to justify early selection of cattle for targeted markets and growth paths. However, there is opportunity for processors to use fat biopsy and objective colour measurement techniques in the selection and purchase of cattle for high priced markets. },
	issn = {1176-5283},
	author = {Boom CJ and Sheath GW}
}
@conference {40951,
	title = {Use of teaser ram effect to advance lambing date in a farm systems study},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {57},
	year = {1997},
	month = {Jan},
	pages = {256-257},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The normal onset of seasonal oestrous behaviour in Romney derived breeds can be advanced by the use of teaser rams and social facilitation. This technique was used, as part of a farm systems trial, to advance the start of lambing from September 1 to August 1. In the first year, the use of Dorset rams at ratios of 0, 3, 6 and 9 per 100 ewes resulted in 0, 72, 81 and 86\% respectively of ewes ovulating at the silent oestrous. In the following year, a ratio of 8\% was used in combination with CIDRs after the silent oestrous. This extra manipulation gave no advantage in terms of ewes lambing and ewes lambing multiples. Use of Coopworth rams instead of Dorsets and priming the teaser rams by exposure to oestrogen treated spayed ewes likewise had little impact. Over all years, teasing resulted in a similar proportion of ewes lambing (87\%) compared to the later lambing non-teased groups (89\%). However, the early groups had only 37\% multiple births compared to the late lambing ewes (48\%, P<0.01). The 31 day advance in start mate date in the early ewes resulted, on average, in a 27 day advance in mean lambing date (P<0.01). When weaned on the same date the early lambs were 2.27 kg heavier than the late lambs (P<0.01). },
	issn = {1176-5283},
	author = {Smeaton DC and Webby RW and Sheath GW}
}
@conference {40646,
	title = {The role of systems research in animal science},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {54},
	year = {1994},
	month = {Jan},
	pages = {417-422},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {This paper presents challenges to the way we conduct experimentation  
in animal science.  The theme of the paper is to show the benefits of using  
systems research methods in both our basic and applied animal science.  The  
need for more accurate prediction of biological processes to achieve future  
breakthroughs in animal production is postulated.  The use of systems research  
using dynamical systems models in our basic science to better understand and  
predict the outcome of complex biological processes is discussed.  In the  
applied science context, difficulties in translating basic (component) research  
results into recommendations for improved farm performance are emphasised.   
Equally, difficulties in designing interpretable farm system experiments are  
acknowledged.  Finally, examples are given of the benefits of using whole farm  
models to integrate component results and create a link between component  
research and improved farm system, field, experimental approaches. 
 },
	issn = {1176-5283},
	author = {McCall DG and Sheath GW and Pleasants AB}
}
@conference {40050,
	title = {Facial eczema in hill country - potential toxicity and effects on ewe performance},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {47},
	year = {1987},
	month = {Jan},
	pages = {45-48},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Milk responses to selenium supplementation were measured in 12 dairy herds of low selenium status as indicated by blood selenium concentrations of less than 150 nmol/l (<12 ug/l). In 4 of the herds milk responses were measured for 2 successive seasons. Milk volume responses to selenium varied from -2.6\% to +10.4\% (mean +4.6\%) and milk fat responses from -4.0\% to +10.2\% (mean +3.7\%). Significant (P<0.05) milk volume responses occurred on 2 farms in the first season and milk fat responses on 2 farms in the second season. A negative relationship (P<0.01) was found between milk fat response (\%) to selenium (FatSe) and blood selenium concentration (nmol/l) (BSe) for herds in their first season of supplementation of:- FatSe) = 9.6 - 0.059 BSe. There was no relation between these parameters in the second season of supplementation.},
	issn = {1176-5283},
	author = {Sheath GW and Webby RW and Boom RC}
}
