1. Laboratory of Metabolic Manipulation of Herbivorous Animal Nutrition, College of Animal Science and Technology, Yangzhou University, Yangzhou, China;
2. Joint International Research Laboratory of Agriculture & Agri-Product Safety, Yangzhou University, Yangzhou, China;
3. Jiangsu Engineering Technology Research Center of Mutton Sheep & Goat Industry, Nanjing Agricultural University, Nanjing, China