@conference {3678,
	title = {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},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {74},
	year = {2014},
	month = {06/2014},
	pages = {142-144},
	address = {Napier},
	abstract = {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-Pati{\~n}o et al. 2011b). Recently it has been shown that enteric methane emissions from sheep are both heritable and repeatable (gCH4/day 0.29 {\textpm} 0.05; repeatability 0.26 {\textpm} 0.02), whether expressed as gross emissions (g/d) or methane yield (emissions per unit of feed dry matter intake, g/kgDMI; Pinares-Pati{\~n}o 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-Pati{\~n}o et al. 2011a)...},
	issn = {1176-5283},
	author = {Elmes SN and Bain WE and Greer GJ and Hickey SM and Young EA and Pickering NK and Rowe SJ and Knowler KJ and Pinares-Pati{\~n}o CS and McEwan JC}
}
@conference {42048,
	title = {Artificial insemination success rates for Meat and Wool New Zealand central progeny test sires},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {68},
	year = {2008},
	month = {Jan},
	pages = {77-78},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Brisbane, Australia},
	abstract = {National progeny testing schemes have become important components of national sheep genetic improvement programmes in Australia, France, and New Zealand (Fogarty et al., 2002; Bib{\'e} et al., 2002; Campbell et al., 2005). In 2001 the Alliance Central Progeny Test was established, this was combined in 2005 with the Elite Lamb Progeny Test to become the Meat and Wool New Zealand Central Progeny Test (CPT). Over the past six seasons, a total of 120 leading industry sires, comprising 14 different breeds, have been mated via artificial insemination. CPT rams are genetically connected via common sires ...Continued },
	issn = {1176-5283},
	author = {McLean NJ and Dodds KG and Knowler KJ and Jopson NB and Behrent M and Logan CM and Muir PD and Shackell GH and McEwan JC}
}
@conference {41723,
	title = {Estimation of autumn live weight breeding values in progeny test datasets when progeny are slaughtered to achieve a target carcass weight},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {67},
	year = {2007},
	month = {Jan},
	pages = {175-179},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Wanaka},
	abstract = {An analysis was undertaken to investigate how lamb autumn live weight breeding values could be calculated from fixed carcass weight progeny tests (e.g. lambs slaughtered at monthly intervals at a threshold carcass weight). Analysis of growth rate is problematic for this progeny test design as the slaughter groups may experience vastly different environmental conditions, both within and between years. Variance components were estimated from an animal model using restricted maximum likelihood (REML) on data from 11,411 Coopworth progeny records and 126 Coopworth sires. The dataset contained records of weaning weight and live weight at four, five and six months of age (LW4, LW5 and LW6, respectively) collected from 1995 to 2004 in a flock run at Woodlands Research Station. The multivariate mixed linear model included lamb birth day deviation as a covariate, sex of lamb, birth rearing rank, age of dam and live weight contemporary group as fixed effects, and sire as a random effect. The WWT model also had dam fitted as a random effect to give WWT direct and maternal effects (WWTdand WWTm). The analysis was then repeated, but with animals records removed from the dataset once they achieved a threshold weight of 31 and 27kg for ram and ewe lambs, respectively, on data prior to or following linear scaling by contemporary group mean. The heritabilities estimated from the full dataset for WWTd, WWTm, LW4, LW5 and LW6 were 0.30{\textpm}0.03, 0.04{\textpm}0.01, 0.49{\textpm}0.02, 0.49{\textpm}0.02 and 0.51{\textpm}0.02, respectively. These traits were highly correlated with both phenotypic and genetic correlations between the direct traits ranging from 84 to 99\%. The same analysis on the two culled datasets resulted in only minor changes the variance components. The correlation between sire breeding values for autumn live weight (LW6) estimated from the full and the two culled datasets were 98.8\% for both models. Autumn live weightbreeding values can be accurately estimated from datasets which include progressive culling if a multivariate live weight analysis is undertaken, and data from all animals measured at each date are used.},
	issn = {1176-5283},
	author = {Jopson NB and McEwan JC and Knowler KJ and Wheeler R}
}
@conference {41156,
	title = {Lamb and ewe performance of East Friesian x Coopworths relative to pure-bred Coopworths},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {60},
	year = {2000},
	month = {Jan},
	pages = {47-50},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {Purebred East Friesians (EF) sires were used in both the 1996 and 1998 matings (n=2 and 4, respectively) to generate 62 and 66 progeny for the two years. These animals were compared with approximately 1000 COOP lambs in each year for growth, ultrasonic fat and muscle depths, wool, dagginess, host resistance to internal parasites, and reproductive performance. For the 1998 mating, one F1 sire and 24 F1 dams were mated to COOP ewes and rams respectively to produce approximately 73 paternal and 33 maternal backcross progeny. Twenty four EF cross ewes were mated in each of the 1998 and 1999 birth years, and reproductive performance recorded. On average, the EF cross progeny had a live weight advantage (P0.05) after adjustment for live weight, but EF cross progeny had significantly lower C and GR measurements. EF cross progeny had lower fleece weight at 12 months (-0.46kg; P<0.001) than COOP. Average dag score differed between sire breeds with EF cross having lower scores (0.4 verses 1.2) compared to COOP. Sire breed differences in resistance to parasites were not significant. Analysis of the limited EF backcross data indicated positive EF direct and maternal effects for weaning weight, negative EF direct effects for dag scores, and negative EF direct and maternal effects for fleece weight. EF cross ewes performed significantly better (P<0.001) in lambs born per ewe lambing than the purebred COOP for both 2-tooth (2.57 cf. 1.84) and mixed-age (2.76 cf. 1.98) classes. The high lambing percentage in EF cross ewes meant that more than 70\% of mixed-age ewes had three or more lambs per lambing, which could result in management difficulties. There was significant overlap in the sire-breed ranges for all traits, meaning selection of sire was more important than breed selection. },
	issn = {1176-5283},
	author = {Jopson NB and Dodds KG and Knowler KJ and Wheeler R and McEwan JC}
}
@conference {40524,
	title = {Heritability of ultrasonic fat and muscle depths in Romney sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {53},
	year = {1993},
	month = {Jan},
	pages = {347-350},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Twelve buffalo (5 bulls \& 7 steers) at c.33 mo of age were compared with 16 Friesian cross cattle (6 bulls \& 10 steers) at c. 29 mo of age. The 2 species had not been run together, but were slaughtered and processed concurrently. Carcass weights were unaffected by species or castration (mean=258.6 kg). Relative to cattle, buffalo had shorter carcasses, higher dressing-out percentages, greater fat depths, more kidney and pelvic fat, and lower eye-muscle areas (all P<0.01). Buffalo had heavier hearts and spleens (P<0.001), and lighter livers and weights of rumen digesta (P<0.001). Buffalo rumen digesta contained fewer particles over 4.0 mm, but the size of particles in the abomasum was similar for both species. Yields of commercial cuts did not differ between buffalo and steers, but cattle steers had more fat trim, less meat, heavier striploins, and a higher ratio of hind-to forequarter meat than bulls (all P<0.05). Relative to the cattle, buffalo carcasses had lighter inside and cube roll cuts, but heavier outside flats, more fat trim, and a higher proportion of forequarter meat (all P<0.05). Buffalo fat was less yellow. Ultimate pH of cube-roll (M. longissimus) samples were higher for bulls than steers within cattle, and higher for cattle than buffalo (each P<0.05), possibly because the buffalo had been handled more. Other quality differences that could have been pH-related were the lower shear values (indicating more tender meat) and lower water-holding capacity (each P<0.01) of buffalo meat.  However, colour (L*, a*, b* values), and sarcomere lengths were similar.  Intramuscular fat levels were similar for meat from buffalo and cattle steers, but were much lower for bull beef. This is the first set of cattle/buffalo comparative data for carcass and meat quality collected under New Zealand conditions and will be of value when evaluating the role of Buffalo in this country.},
	issn = {1176-5283},
	author = {McEwan JC and Clarke JN and Hickey SM and Knowler KJ}
}
