肉用西门塔尔牛群体生长曲线拟合及体重与体尺相关性分析的研究

The Growth Curve Fitting and the Correlation Analysis between Body Weight and Body Measurements in Chinese Simmental Beef Cattle Population

旨在对内蒙古乌拉盖地区肉用西门塔尔牛群体的体重和体尺等性状进行分析,研究其生长发育规律并构建通过体尺预测体重的回归方程。本研究测定了2 162头肉用西门塔尔牛从出生到20月龄的体重、体高、十字部高、体斜长、胸围和腹围,利用Logistic、Brody、Gompertz和Bertallanffy 4种模型拟合其生长曲线,分别估算出4种曲线方程中的相关参数,并进行体重与体尺的相关性与回归分析。结果表明,4种曲线模型对肉用西门塔尔牛体重和体尺生长过程均有较好的拟合度(R^2>0.98),但对于不同的性状,最佳拟合模型不同。体重与体尺相关关系表明,体重与体斜长、胸围、腹围的相关性较高,其中体重与胸围的相关系数最高(0.958 55)。其体尺与体重之间呈极显著正相关关系。预测体重回归方程为Y=-366.485 70+1.307 37 X_3+3.896 12 X_4-0.417 50 X_5。研究表明,Gompertz和Bertallanffy两种模型对体重的拟合优于其他两种模型,Brody模型对体高、体斜长、胸围、腹围和十字部高的拟合效果均是最优。体重预测回归方程具有统计学意义,为肉用西门塔尔牛群体的进一步选育提供数据基础。

This experiment was conducted to investigate the growth rule of the body weight and body size traits for Chinese Simmental beef cattle population in Ulgai of Inner Mongolia,and to construct the regression equation of body weight by body size.We measured the growth traits of2 162 Simmental cattle including body weight,withers height,hip height,body length,chest circumference and abdominal girth from birth to 20 month old.Using Logistic,Brody,Gompertz and Bertallanffy models,we fitted the growth curves of these traits,and calculated the related parameters in the 4 curve equations,respectively.We also conducted correlation and regression analysis between body measurements and body weight.The results showed that all of the 4 kinds of growth curve fitting models in Chinese Simmental beef cattle had good fitting degree（R^20.98）for the growth of body measurements and body weight,but for different traits,the optimalfitting model was different.The correlation analysis between body weight and body measurements showed that correlations between body weight and body length,chest circumference,abdominal girth were higher,respectively.The correlation coefficient between body weight and chest circumference was the highest（0.958 55）.The extremely significant correlations between body measurements and body weight were observed.The regression equation predicting body weight was Y=-366.485 70＋1.307 37 X_3＋3.896 12 X_4-0.417 50 X_5.The results indicated that the fitting for body weights of Gompertz and Bertallanffy were better than the other two models,and the Brody model was the best for fitting the body height,body length,chest circumference,abdominal girth and hip height.The regression equation predicting body weight was proved to be of statistical significance,which will provide the data basis for the further breeding of Chinese Simmental beef cattle.