1. State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
2. Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
3. Hubei Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, People's Republic of China