1. Colloge of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; 2. Farming Bureau of Hubei Province, Wuhan 430070, China; 3. Jiangsu Yanjiang Institute of Agricultural Sciences, Nantong 226541, China; 4. Farming Bureau of Fang County of Hubei, Fang County 442100, China; 5. Farming Bureau of Shiyan of Hubei, Shiyan 442100, China