1. G. B. Chang:
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, China
2. R. Chen:
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, China
3. Y. R. Qin:
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, China
4. Y. Zhang:
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, China
5. A. Q. Dai:
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, China
6. G. H. Chen:
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, China