新疆褐牛体尺性状指标与体重的主成分分析

选择30头18月龄左右新疆褐牛进行体尺、体重测定，选择累计贡献率达89.505%的7个主成分进行分析。结果表明，新疆褐牛体尺指标尻长、腰角宽、髋宽、坐骨宽及体重的变异较大，选育潜力大；体重与体斜长、胸围、腰角宽、髋宽等指标存在极显著相关（P＜0.01），与管围呈显著相关（P＜0.05）；从主成分的特征根与累计贡献率来看，第1至第3主成分起主导作用的第1主成分主要反映体型外貌特征，第2主成分主要反映尻部特征，第3主成分主要反映后躯特征。

The Principal Component Analysis of Xinjiang Brown Cattle Body Measurement Trait

Multivariate factor analysis and principal component analysis were used to decompose the correlation matrix of body measurement trait of 30 Xinjiang Brown cattle of age about 18 months, then indexes of Xinjiang Brown cattle body measurement trait were studied by the principal components analysis, the 7 principal components which contributing rate accumulated up to 89.505% were chose. The results showed that there was big potential of mass selection for the rump length, hip width, thurl width, pin bone width and body weight, there were high significant correlation among body weight，body length, heart girth, hip width（P＜0.01）, and there was significant correlation with thurl width（P＜0.05）. The first principal component reflected the entire growth and development condition of Xinjiang Brown cattle, the second principal component reflected rump characteristics, the third principal component reflected back body characteristics.