1. Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu, P. R. China
2. College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, P. R. China
3. Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing, Jiangsu, P. R. China