@article {3672,
	title = {Impact of trait genetic gains on methane emissions from NZ beef and dairy farms},
	journal = {New Zealand Journal of Animal Science and Production},
	volume = {80},
	year = {2020},
	month = {09/2020},
	pages = {76-79},
	address = {Online},
	abstract = {The objective of this study was to provide estimates of the impact of trait genetic gains on methane emissions from NZ dairy and
beef farms. The effect of each trait on gross emissions (GE) and emissions intensity (EI) was modelled by estimating effects of trait
changes on per-animal feed consumption and the associated methane production, per-animal production and numbers of animals in
the system. In dairy, the annual gross emissions per breeding cow associated with genetic change were estimated to increase for all
traits except Residual Survival and Fertility. Conversely, emission intensity values were estimated to decrease for Milk Fat, Milk
Protein, Milk Solids, Residual Survival, Fertility and Body-condition Score (BCS) as genetic merit improves. In beef production,
increases in genetic merit for cow mature weight, cow BCS, cow calving ease and heifer pregnancy were estimated to increase the
annual gross emissions per breeding cow. Conversely, an increase in merit associated with stayability and gestation length reduced
annual gross emissions per breeding cow. The effect of increasing carcase weight on gross emissions depended on whether the
faster growth performance was used to slaughter the animal earlier, or to take the animal through to heavier finishing weights.

Keywords: methane; emissions intensity; gross emissions; dairy; beef},
	issn = {1176-5283},
	author = {Proctor LE and Archer JA and Sise JA and Zhang X and Crowley JJ and Amer PR}
}
@conference {3672,
	title = {The effect of grazing high-sugar ryegrass on lamb performance},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {75},
	year = {2015},
	month = {07/2015},
	pages = {235-238},
	address = {Dunedin},
	abstract = { 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.},
	issn = {1176-5283},
	author = {Proctor LE and Craig HJB and McLean NJ and Fennessy PF and Kerslake JI and Behrent MJ and Chuah JCL and Campbell AW}
}
