Effects of nutrition level of concentrate-based diets on growth performance and carcass characteristics of Hainan black goats.

This study assessed the effects of different nutrition levels of diets on growth performance and carcass characteristics of Hainan black goat. Twenty-four goats were divided into six diet treatments, which consisted of two levels of crude protein (CP; 15 and 17 %) and three levels of digestive energy (DE; 11.72, 12.55, and 13.39 MJ/kg). The results revealed that 17 % CP significantly (P < 0.05) increased ADG and improved FCR compared with 15 % CP. Therefore, the CP levels of diet affected growth performance. CP and DE levels in the diet had no significant effects (P > 0.05) on carcass characteristics of the goats. The mRNA expression levels of insulin-like growth factor 1 in muscle tissues increased with increasing CP and DE levels (P < 0.05).