奶牛乳房性状的数量化理论分析

ANALYSIS OF QUANTIFICATION THEORY FOR UDDER TRAITS IN DAIRY CATTLE

本文对275头奶牛的26个性状进行了多元回归和数量化理论Ⅰ的分析。结果为:乳房曲长、乳井直径和乳静脉直径大小与产奶量相关极其密切,其中乳房曲长是乳房容积的代表性状。腹围与各项产奶量相关显著,可作为外貌鉴定中的重要性状。根据26个性状与305天产奶量的多元回归分析,得方程式:(?)=6567.43-169.85X_(14)-32.6X_(20)+6.8X_(24)+6.44X_(250)R值为0.66,说明该式对估计305天产奶量具有一定准确性。

Twenty six traits from 275 cows were analysed by the methods of multiple regression and quantification theory I . The result shows that the curve length of the udder and the diameters of milk well and mammary vein were very closely related to the milk yield, among which the curve length of the udder was a representative trait of the udder volume. The abdomen circumference and milk yields were significantly correlated. Therefore, the abdomen circumference was often used as an important trait in the appearance appraisal. By the multiple regression analysis between the 26 traits and the milk yield in 305 days, a equation was obtained: Y = 6567.43 - 169.85X14 - 32.6X20 + 6.80X24 + 6.44X25 The R value was 0.66. This indicates that the above equation has certain accuracy in the estimation of milk yield in 305 days.