Growth law and growth curve fitting of Qianhua Mutton Merino

A new species in China, the Qianhua Mutton Merino is a breed of sheep that is farmed for both meat and wool. To understand the growth and development of Qianhua Mutton Merino sheep under indoor feeding conditions, the weights of rams and ewes aged 0～24 months were measured, and the results were subjected to fitting analysis using logistic and Gompertz models. The results showed that the degree of fitting R² of the two models was above 0.95, with good fitting effects. The fitting effects of the Gompertz model were better than those of the Logistic model on body weight; the weight inflection point of rams and ewes were 6.37 months and 2.44 months, respectively, with a weight of 49.68 and 23.02 kg, and a maximum daily gain of 218.59 and 249.38 g·d⁻¹, respectively; the weight of rams was significantly higher than that of the ewes at all ages. The absolute growth peaks of weight appeared in rams at 3～6 months and ewes at 0～3 months, which were consistent with the results of the growth model fitting. The results of this study provide a theoretical reference for establishing the early selection and breeding management strategies for the Qianhua Mutton Merino.