Haslin Emmanuelle, Corner-Thomas Rene A, Kenyon Paul R, Pettigrew Emma J, Hickson Rebecca E, Morris Steve T, Blair Hugh T
School of Agriculture and Environment, Massey University, Palmerston North 4474, New Zealand.
Animals (Basel). 2021 Dec 7;11(12):3486. doi: 10.3390/ani11123486.
This experiment examined the effect of breeding heavier ewe lambs on lamb production and their efficiency over their first three breeding seasons. Two groups of ewe lambs were bred at seven months of age at an average pre-breeding live weight of either 47.9 ± 0.36 kg (heavy; = 135) or 44.9 ± 0.49 kg (control; = 135). Ewe live weight, number of lambs born and weaned, and lamb live weight were recorded until 39 months of age, and efficiency was calculated for each ewe. Although the number and lamb weaning weight did not differ between treatments over three years, when data were pooled, heavier ewe lambs at breeding weaned a greater number of lambs over the three-year period. The total lamb weaning weight over the three-year period increased by 2% for each additional kilogram at ewe lamb breeding. Breeding heavier ewe lambs had no effect on efficiency. These results suggest that although breeding heavier ewe lambs had a positive effect on lamb production over the three-year period, it had no effect on efficiency. Before final recommendations can be made, lifetime performance and longevity to five years of age of heavier ewe lambs at breeding are required.
本试验研究了培育体重更重的母羊羔羊对其前三个繁殖季节产羔性能及其效率的影响。两组母羊羔羊在7月龄时配种，配种前平均活重分别为47.9±0.36千克（重体重组；n = 135）或44.9±0.49千克（对照组；n = 135）。记录母羊体重、产羔数、断奶羔羊数和羔羊体重直至39月龄，并计算每只母羊的效率。虽然三年间各处理的产羔数和羔羊断奶体重没有差异，但合并数据后，配种时体重更重的母羊羔羊在三年期间断奶的羔羊数量更多。母羊羔羊配种时每增加1千克体重，三年期间的总羔羊断奶体重增加2%。培育体重更重的母羊羔羊对效率没有影响。这些结果表明，虽然培育体重更重的母羊羔羊在三年期间对产羔性能有积极影响，但对效率没有影响。在做出最终建议之前，需要了解配种时体重更重的母羊羔羊到5岁时的终生生产性能和寿命情况。
