Reed P D, Van Vleck L D
J Dairy Sci. 1987 Apr;70(4):837-41. doi: 10.3168/jds.S0022-0302(87)80081-4.
Heritability estimates, by year of freshening of daughter, were obtained from daughter-dam and granddaughter-granddam regressions using 61,482 triply matched first lactations of artificially sired Holstein cows obtained from the Northeast Dairy Records Processing Laboratory. After adjusting for herd-year-season effects, residual effects may include additive and other genetic effects of the animal, maternal effects, cytoplasmic effects, and other environmental effects. Analysis of residuals showed that cytoplasmic effects accounted for no variation in milk and fat yield and fat percent. Weighted yearly heritability estimates and standard errors from daughter on dam regressions were .35 +/- .01 for milk yield, .30 +/- .01 for milk fat yield, and .63 +/- .01 for milk fat percent and from daughter on granddam regressions were .34 +/- .03 for milk production, .28 +/- .03 for milk fat production, and .55 +/- .03 for milk fat percent. The differences between daughter-dam and daughter-granddam heritability estimates, which estimate twice the fraction of variance due to cytoplasmic effects, were negative and not statistically significant for milk fat yield and also were negative but highly significant for milk fat percent.
通过女儿产犊年份进行遗传力估计，是利用从东北奶牛记录处理实验室获取的61482头人工授精荷斯坦奶牛的三重匹配首次泌乳数据，通过母女回归和祖孙回归得到的。在对畜群-年份-季节效应进行调整后，残差效应可能包括动物的加性和其他遗传效应、母体效应、细胞质效应以及其他环境效应。残差分析表明，细胞质效应在产奶量、乳脂产量和乳脂率方面没有造成变异。母女回归得到的加权年度遗传力估计值和标准误为：产奶量为0.35±0.01，乳脂产量为0.30±0.01，乳脂率为0.63±0.01；祖孙回归得到的为：产奶量为0.34±0.03，乳脂产量为0.28±0.03，乳脂率为0.55±0.03。母女和祖孙遗传力估计值之间的差异，该差异估计了细胞质效应导致的方差比例的两倍，对于乳脂产量为负值且无统计学意义，对于乳脂率也为负值但具有高度统计学意义。
