Notter D R, Tier B, Meyer K
Animal Genetics and Breeding Unit, Armidale, NSW, Australia.
J Anim Sci. 1992 Aug;70(8):2359-65. doi: 10.2527/1992.7082359x.
Weaning weight records of 44,357 Australian Angus calves produced by 1,020 sires in 90 herds were used to evaluate the importance of sire x herd interactions. Models fitted fixed effects of contemporary group (herd-year-date of weighing subclass), sex, calf age, and dam age and random effects of sire or of sire and sire x herd interaction using REML. Effects of standardizing the data, including sire relationships and including dam maternal breeding values (MBV) as a covariate were also investigated. Sire x herd interactions were found (P less than .05) in all cases and, in the most complete model, accounted for 3.3% of phenotypic variance. Across-herd heritabilities ranged from .19 to .28. Differential nonrandom mating among herds seemed to occur in the data. Significant sire x herd effects were observed for dam MBV, and adjustment for dam MBV yielded the smallest estimates of interaction variance and across-herd heritability. If sire x herd interactions were due only to genotype x environment interaction, within-herd heritabilities would range from .33 to .49. These estimates are larger than previously reported estimates. Thus, unreported environmental effects common to progeny of individual sires may also be involved in the observed interaction but could not be disentangled from true genotype x environment interaction effects using these data. Results of these analyses suggest that some accommodation of sire x herd interaction effects on weaning weight may be needed in beef cattle genetic evaluations, but a compelling case for development of herd-specific breeding value prediction cannot be made.
利用90个牛群中1020头种公牛所产44357头澳大利亚安格斯犊牛的断奶体重记录，评估种公牛×牛群互作的重要性。模型采用REML拟合当代组（牛群-年份-称重亚类日期）、性别、犊牛年龄和母牛年龄的固定效应，以及种公牛或种公牛与种公牛×牛群互作的随机效应。还研究了对数据进行标准化处理的效果，包括种公牛亲缘关系以及将母牛的母本育种值（MBV）作为协变量纳入分析。在所有情况下均发现了种公牛×牛群互作（P小于0.05），在最完整的模型中，其占表型方差的3.3%。群体间遗传力范围为0.19至0.28。数据中似乎存在牛群间的差异非随机交配现象。对于母牛的MBV，观察到显著的种公牛×牛群效应，对母牛MBV进行校正后，互作方差和群体间遗传力的估计值最小。如果种公牛×牛群互作仅归因于基因型×环境互作，群体内遗传力范围将为0.33至0.49。这些估计值比之前报道的估计值要大。因此，个体种公牛后代共有的未报告环境效应可能也参与了观察到的互作，但利用这些数据无法将其与真正的基因型×环境互作效应区分开来。这些分析结果表明，在肉牛遗传评估中可能需要对种公牛×牛群互作对断奶体重的影响进行一些考量，但无法有力地证明需要制定特定牛群的育种值预测方法。
