皮特兰猪生长发育规律及其生长曲线拟合分析

试验旨在研究皮特兰猪的生长发育规律并对其生长曲线进行拟合。利用奥斯本测定系统，导出皮特兰猪（122头公猪和129头母猪）从出生到210 d的7个时间点的生长发育数据，并以此数据为基础分别利用Logistic、Bertalanffy、Gompertz 模型进行生长曲线拟合。结果显示，皮特兰猪体重增长符合S型生长曲线，110~150日龄为快速增长期，出生后越早期相对生长强度越大，之后随着日龄增加逐渐降低。3种拟合模型均获得较理想效果，其中Logistic模型对皮特兰猪拟合度最高（R²=0.9815，母猪），拟合结果最接近真实情况；其他两种模型也相对较高，为0.9589（母猪）和0.9698（母猪），均高于0.95。因此Logistic模型最适合法系皮特兰猪的生长发育过程，对方程进行求导，可得公、母猪最大日增重分别为1.051和0.983 kg/d。在其拟合生长曲线中，皮特兰公、母猪拐点日龄分别为114.72和114.89 d，体重分别为65.30和63.00 kg。

Analysis of Growth Development and Growth Curve Fitting of Pietrain Pig

This experiment was aimed to study the growth development and fit the growth curve of Pietrain pig. The body weight records were collected by Osborne FIRE system to study its regularity growth development (122 boars and 129 sows).The rapid growth period was centralized between 110 and 150 d, and the growth of Pietrain pig was fitted the typical S-curve. The relative growth intensity was higher for younger pigs, then decreased gradually. Three non-linear models including Logistic,Bertalanffy and Gompertz were utilized to fit the growth curve of Pietrain pig, though all the three models had good fitness,and R² of the models (Logistic,Bertalanffy,Gompertz) for sow were 0.9815, 0.9589 and 0.9698, respectively. The results showed Logistic model played better for achieving the real observations. According to the fitting growth curve, the age of inflection value of boar and sow were 114.72 and 114.89 d,the weight of inflection value were 65.30 and 63.00 kg, the highest daily gain were 1.051 and 0.983 kg/d,respectively.