Dimov G, Albuquerque L G, Keown J F, Van Vleck L D, Norman H D
Department of Animal Science, University of Nebraska, Lincoln 68583-0908, USA.
J Dairy Sci. 1995 Apr;78(4):939-46. doi: 10.3168/jds.S0022-0302(95)76709-1.
An animal model with a REML algorithm was used to estimate variances of additive genetic effects and interaction effects of sire and herd. Milk and fat yields were analyzed for first, second, and third lactations of Holsteins from California, New York, and Pennsylvania. Twenty samples of data were used in the study: 10 from California, 4 from New York, and 6 from Pennsylvania. Mean number of lactations per sample was 36,820 from 18,189 cows in 156 herds. Mean fractions of phenotypic variance of interaction effects of sire and herd for milk and fat yields were .015 and .019 for first lactation and .019 and .021 for all (up to three) lactations rather than the .14 used for national genetic evaluations in the US. Mean heritability estimates for milk and fat yields were .26 and .24 for first lactation and .21 and .21 for all lactations in California and .34 and .35 for first lactations and .28 and .29 for all lactations in New York. Sums of variances of permanent environmental and interaction effects of sire and herd were similar to those used for national genetic evaluations in the US. Analysis of another 10 samples from California and 10 samples from New York showed only slightly different fractions of phenotypic variance for milk yield for interaction effects of sire by herd, sire by herd by year, and sire by herd by year by season: .023, .027, and .037 for California and .023, .017, and .023 for New York, respectively.
使用带有REML算法的动物模型来估计父本和牛群的加性遗传效应及互作效应的方差。对来自加利福尼亚州、纽约州和宾夕法尼亚州的荷斯坦奶牛的头胎、二胎和三胎泌乳期的产奶量和乳脂产量进行了分析。本研究使用了20个数据样本：10个来自加利福尼亚州，4个来自纽约州，6个来自宾夕法尼亚州。每个样本的平均泌乳次数为36,820次，来自156个牛群中的18,189头奶牛。头胎泌乳期产奶量和乳脂产量的父本与牛群互作效应的表型方差平均比例分别为0.015和0.019，所有（最多三胎）泌乳期的该比例分别为0.019和0.021，而非美国全国遗传评估所使用的0.14。加利福尼亚州头胎泌乳期产奶量和乳脂产量的平均遗传力估计值分别为0.26和0.24，所有泌乳期的分别为0.21和0.21；纽约州头胎泌乳期的分别为0.34和0.35，所有泌乳期的分别为0.28和0.29。永久环境效应以及父本与牛群互作效应的方差总和与美国全国遗传评估所使用的相似。对另外10个来自加利福尼亚州的样本和10个来自纽约州的样本进行分析表明，父本×牛群、父本×牛群×年份以及父本×牛群×年份×季节互作效应的产奶量表型方差比例仅有细微差异：加利福尼亚州分别为0.023、0.027和0.037，纽约州分别为0.023、0.017和0.023。
