1. Institute of Animal Science and Veterinary Medicine, Yantai Academy of Agricultural Sciences, Yantai, China
2. College of Animal Science and Technology, Jiangxi Agriculture University, Nanchang, China
3. Yantai Animal Disease Prevention and Control Center, Yantai, China
4. Yantai Agricultural Technology Extension Center, Yantai, China
5. Haiyang Animal Disease Prevention and Control Center, Yantai, China