中国荷斯坦牛乳房性状、体型总分与产奶性状的相关分析

Correlations Analysis among Udder Traits, Final Score and Milk Production Traits in Chinese Holstein Dairy Cows

研究利用武汉市58头公牛的971头女儿2006—2007年间的体型性状鉴定记录及2001—2007年间的生产性能测定记录,配合动物模型,采用REML方法进行参数估计,探讨了乳房性状、体型总分与产奶性状之间的关系。结果表明:乳房性状与产奶性状之间的表型相关较小。后乳房宽度与产奶性状之间存在强的遗传正相关(0.44～0.89)。后乳房高度与305 d产奶量(0.27)、305 d乳脂量(0.16)存在遗传正相关,而与305 d乳蛋白量(-0.32)存在遗传负相关。前乳房附着与产奶性状基本不存在相关。悬韧带与305 d产奶量存在遗传正相关(0.79)。乳房深度与305 d产奶量存在遗传负相关(-0.20)。体型总分与305 d产奶量、305 d乳脂量、305 d乳蛋白量存在较强的遗传正相关,故加强乳房性状和体型总分的选择对提高奶牛的生产性能有益。

The objectives of this study were to estimate phenotypic and genetic parameters between selected type traits and milk production traits by applying animal models through REML algorithm in Holstein dairy cows.This study included linear type data from 971 daughters of 58 sires collected from 2006 to 2007,and milk production data of 971 cows from 2001 to 2007 derived from Wuhan city.The results showed that phenotypic correlations between udder traits and milk production traits were weak.Positive genetic correlations were found among rearudder width,305 d milk yield,305 d fat yield,305 d protein yield（0.44~0.89）.Rear udder height and 305 d milk yield（0.27）,305 d fat yield（0.16） had positive genetic correlations,but it displayed a negative genetic correlation to 305 d protein（-0.32）.There were no correlations between fore udder attachment and milk production traits.Positive genetic correlation between median suspensory and 305d milk yield（0.79）,slightly genetic correlations between median suspensory and 305 d fat yield or 305 d yield protein yield were estimated.The genetic correlation between udder depth and 305 d milk yield was-0.20.The genetic and phenotypic correlations between final score and 305 d milk yield,305 d fat yield,305 d yield protein yield were positive and moderate.So,increased emphasis on selection for udder traits and final score would bring great benefits to improve milk production.