奶牛繁殖性状的育种值估计

Estimation of Breeding Values of Dairy Cow Reproductive Characters

[目的]奶牛繁殖性状的育种值估计及比较不同育种值估计方法的准确性。[方法]利用北京市8个黑白花奶牛群的头胎繁殖性状资料,用BLUP法估计了公牛繁殖力的育种值;利用20头公牛的2299条与配母牛头胎繁殖性状资料,估计了公牛雄性繁殖力的育种值;利用19头公牛的2001条女儿的头胎繁殖性状资料,估计了公牛雌性繁殖力的育种值。分别比较了考虑场、年、季之间互作效应的和未考虑场、年、季之间互作效应,用最小二乘法事先矫正了场、年、季效应这3种方法的育种值估计准确性。[结果]考虑场、年、季之间互作效应时的准确性最高,未考虑时的准确性最低。[结论]估计公牛繁殖性能的育种值时,应事先或模型中加以剔除这些固定效应。

[Objective] The paper was conducted to estimate the breeding values of dairy cow reproductive characters and to compare the accuracy of different estimate methods of breeding values. [Method] With the first born reproduction of 8 Holstain herd records in Beijing, the fertility breeding values of bulls were estimated by using BULP method. With 2,299 cows from 20 sires records on the first born reproduction of match cow, the male fertility breeding values of bulls were estimated. And the bull＇s female fertility breeding values were estimated with 2,001 cows from 19 sires records. The accuracies of the breeding value estimations under 3 models, namely considering hard-year-season effects, without herd-year-season effects and using Least Square method were compared. [Result] Result showed that the method of taking herd-year-season into account had highest accuracy, while that of not taking herd-year-season into account had lowest accuracy. [Conclusion] When estimating the breeding values of bull＇s fertility, these fixed effects should be rejected beforehand or in the model.