Growth and development characteristics and growth model of Hu sheep in the fattening period

The body weight and body size of 207 male Hu lambs aged 0～180 days were measured under house feeding conditions, and three models, Logistic, Gompertz, and Von Bertalanffy, were used to fit the growth process of male Hu lambs from 0 to 180 days. We then analyzed and compared the growth parameters and model predicted values to evaluate the growth and development characteristics of Hu sheep. The results showed that the body weight and body size of male Hu lambs increased gradually from birth to 180 days. The male Hu lambs were at the peak of body weight growth from 0 to 160 days, but the development of body size occurred in stages, and the growth range of body size was different in each period. There was a significant positive correlation between body weight and body size (P < 0.01), and the correlation coefficient between body weight and chest circumference was the highest, followed by body length, body height, and circumference of cannon bone. The Logistic, Gompertz, and Von Bertalanffy models could fit the growth trend of Hu sheep from 0 to 180 days old, with R² ≥ 0.995. By comparing the measured body weight with the predicted body weight estimated by the model, it is found that the Gompertz growth model has a more suitable fitting effect.