新疆褐牛母牛早期生长曲线拟合研究

Fitting of the Early Growth Curve for Growing Xinjiang Brown Cattle

为探讨新疆褐牛母牛早期生长发育规律，并拟合其生长曲线。，本研究收集新疆塔城地区种牛场1091头次1～18月龄新疆褐牛母牛体高、体斜长、胸围、管圊和体重记录，分别采用Logistic、Gompertz、Brody、Bertalanffy4种非线性模型时其生长情况进行拟合与分析。结果表明：4种曲线模型的拟合效果郜很好（R2〉0．8600），通过比较各个性状的拟合度，Gompertz模型对新疆褐牛母牛体高的拟舍效果最佳，拟合度为0．9993；Bertallanfly模型对体斜长和体重的拟合效果最佳，拟合度分别为0．9999、0．9997；Brody模型对胸围和管围的拟台效果最佳，拟合度分别为0．9996、0．9983，由Bertallanflfv模型计算出新疆祸牛母牛的拐点月龄和拐点体重分别为4．91月龄和127．08kg。新疆褐牛母牛在1～12月龄，特别是1～6月龄生长发育速度快，生长强度大，随着月龄的增加，其生长速度和生长强度逐渐下降.

The data were collected frmn the records of body height, body length, chest circumterence, cannon circumference and body weight of 1091 growing Xinjiang Brown cow with 1-18 months old in cattle farm of Tacheng area. In order to investigate the early growth and development of Xinjiang brown cattle and to fit the growth curve and also 4 nonlinear models named as Logistic, Gompertz, Brody, and Bertalanffy were used to fit and analyze its growth. The results showed that the fitting effect of the 4 kinds of curves models were very good （R2〉0.860 0）, the fitting effect of Gompertz model on the body height of Xinjiang brown cow was the best by comparing the fitting degree of each character, and the fitting degree was 0.999 3; The Bertallanffy model was the best to fitting the body length and body weight growth of Xinjiang Brown cow, the degree of fitting R2 were 0.999 9 and 0.999 7, respectively. The Brody model was the best to fitting the chest circumference and cannon circumference growth of Xinjiang Brown cow, the degree of fitting R2 were 0.999 6 and 0.998 3, respectively. The inflection point of the age body weight of the Xinjiang brown cow from the Bertallanffy model was 4.91 months old and 127.08 kg.The growth and development were rapid and growth intensity was big at the months of age of 1-12 , especially at the months of age of 1-6 growth faster. With the increase of age, the growth rate and the growth intensity decreased gradually. This study will provide basic data for the breeding and improvement work of Xinjiang brown cattle.