@conference {41939,
	title = {Quantitative genetic selection for twinning rate in ewes},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {66},
	year = {2006},
	month = {Jan},
	pages = {429-433},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Napier},
	abstract = {Data from 19 recorded sheep flocks were included in this study involving 324 thousand lambings from the 1970{\textquoteright}s up until the 2004 lambing season. The genetic correlation between number of lambs born, and a triplet trait coded as 1 for ewes lambing triplets or higher multiples, and 0 for ewes lambing singles or twins was estimated separately over 13 data sets. Genetic correlation estimates ranged between 0.78 and 0.95 with all but two dataset estimates differing from 1.00 by two or more standard error intervals. Flock differences in the relationship between mean NLB and the proportion of ewes lambing twins were also investigated through an analysis of sire mean results. Strong evidence was found for within flock genetic variation in twinning incidence that is independent of mean NLB. This is different to the clear relationship that exists between mean litter size of a group of ewes and the proportion that lamb twins. There were also meaningful differences across-flocks in the proportions of ewes lambing twins after accounting for the effects on twinning percent of flock mean litter size. Our analyses suggest that simple selection strategies such as screening in twin lambing ewes from a commercial flock, and/or, only using twin-born rams in the breeding flock, will be relatively ineffective for improving twinning rates. A recommendation arising from the study is that genetic evaluation tools for twinning be made available to New Zealand sheep breeders. These tools would allow breeders to select for decreased triplets without compromising genetic progress in other traits including mean number of lambs born. },
	issn = {1176-5283},
	author = {Amer PR and Bodin L}
}
@conference {40003,
	title = {Organisation of sheep breeding in France},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {46},
	year = {1986},
	month = {Jan},
	pages = {105-110},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Grazing yearling steers with ewes between November and March led to improved ewe and steer live-weight gains compared to grazing them in mobs by themselves. This occurred on both steep and easy land, and on each of 3 grazing pressures; residuals of either 1200, 1700 or 2300 kg DM/ha with pre-grazing masses 1200kg DM/ha greater than residuals. Ewe live-weight gains were 56, 67 and 82 g/d where sheep/cattle ratios were 100/0, 80/20 and 60/40, on a stock unit basis. Steer live-weight gains were 0.65, 0.55 and 0.51 kg/d for the 80/20, 60/40 and 0/100 sheep/cattle ratio treatments. Associated with improved ewe and steer performance under mixed grazing on steep country was a decrease in the area of pasture rejected at 40\% cattle stock units compared to 0\% and 20\% cattle (26\% v 32\%). On easy country, the amount of clover in the pasture increased by 5 and 19 percentage units at 40\% and 100\% cattle stock units respectively. The results suggested that between 20\% and 40\% cattle stock units in a mob may be needed to obtain high levels of ewe and steer live-weight gain in late spring-summer.},
	issn = {1176-5283},
	author = {Bodin L and Flamant JC and Elsen JM}
}
