1. College of Animal Science and Technology, Henan University of Animal Husbandry and Economy, Zhengzhou 450046, China
2. Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
3. Animal Husbandry Station of the Guangxi Zhuang Autonomous Region, Nanning 530221, China
4. Henan Institute of Agricultural, Animal and Aquatic Products Inspection & Testing Technology, Zhengzhou 450046, China