安格斯牛体重和体尺性状生长曲线拟合与相关性分析

为充分了解安格斯牛生长发育规律,指导饲养管理和提高品种选育,以安格斯牛为研究对象,通过Logistic、Gompertz和Von Bertalanffy 3种曲线模型对0~18月龄安格斯牛体重和体尺性状进行生长曲线拟合分析,并选出最佳生长曲线模型,利用该模型计算体重和体尺的相对生长(R)和绝对生长(G)情况,并对各性状进行简单的相关性分析。结果表明:Von Bertalanffy模型对体重和体尺性状均具有最佳的拟合效果,该模型估计的体重生长拐点为(8.33月龄、245.13 kg);分析各性状的生长发育规律发现,体重和体尺性状的生长强度随月龄的增加逐渐下降,且体重在0~10月龄生长速率达到最大,随后逐渐下降。各性状间的相关性分析表明,体重与体尺性状间均为极显著强正相关(P<0.01),表明体重和体尺性状存在正向选择关系。以上结果体现了安格斯牛早熟性和早期生长强度大、增重速率高的优势。

Growth curve fitting and correlation analysis of body weight and body measurements in Angus cattle

The research was performed on Angus cattle to understand their growth and development patterns, and make relevant predictions to guide feeding management and improve breed selection. Logistic, Gompertz, and Von Bertalanffy models were used to fit the growth curves for weight and body size traits in Angus cattle from 0 to 18 months of age, and to choose the best growth curve model. The model was then applied to calculate relative growth (R) and absolute growth (G) of weight and body size, and simple correlation analysis was performed for each trait. The results showed that Von Bertalanffy model was the best fit for weight and body size traits, and the model estimated the inflection point of weight growth as (8.33 months of age, 245.13 kg). Growth pattern of each trait was analyzed, and it was found that the growing intensity of weight and body size traits decreased gradually with the increase of monthly age, and growth rate of weight reached the maximum from 0 to 10 months of age then decreased gradually. The correlation analysis among the traits showed a strong positive correlation between body weight and body size traits (P<0.01), indicating a positive selection relationship between body weight and body size traits. The above results demonstrated the advantages of early maturity and high early growth intensity and weight gain rate of Angus cattle.