奶牛泌乳曲线的拟合及其模型参数的遗传分析

SIMULATING OF LACTATION CURVES AND GENETIC ANALYSIS OF THEIR MATHEMATICAL MODEL′S PARAMETERS

本实验选取新疆呼图壁种牛场１９８４ 年～１９９５ 年的黑白花牛、西门塔尔牛、蒙贝利亚牛的１８１０ 个泌乳期日奶量资料，采用不累加和累加、１０ｄ 间隔和 ３０ｄ 间隔４ 种数据处理组合方式，使用 Ｓ Ａ Ｓ软件的非线性回归（ Ｎ Ｌ Ｉ Ｎ）过程，对所有个体泌乳过程进行拟合，模型分别为：多项式、逆多项式（①、②）、伍德（①、②）、改进伍德和回归模型。结果 ３０ｄ 间隔数据的全相关指数 Ｒ２ 比１０ｄ 间隔的好，累加数据的 Ｒ２ 比不累加的高，差异非常显著。使用 Ｄ Ｆ Ｒ Ｅ Ｍ Ｌ 对产奶量、模型参数的遗传参数和表型相关及个体育种值采用动物模型进行了计算，结果改进伍德模型的参数 ｂ、ｄ 的遗传力较高，为０３３ 和０３４，与产奶量的遗传相关也很高，为－ ０９９ 和０９８，对用产奶量和模型参数进行育种值排队的秩相关的检验结果为极显著。

lactations′ daily milk yield data of Holstein,Simmental and Montbeliarde cows were collected from 1984 to 1995 in Xinjiang Hutubi Farm.With 10 days and 30 days interval,normal and Grey accumulated method,through SAS software,all individual lactation curves are simulated.Mathematical models used are Polynomial,Inverse polynomial,Wood,Modified Wood and Regressive model.The results show that R 2 value of 30 days interval is higher than 10 days′,and R 2 of accumulated data is much higher than that of normal one.The heritability of parameter b and d of modified Wood model are the highest,0 33 and 0 34,respectively.The genetic correlation between milk yield and b,d are also the highest,-0 99 and 0 98,respectively Ranks of individual breeding value of some parameters are compared with their rank on milk by Spearman′s correlation,it is tested to be significant.