1. College of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China
2. Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
3. Yangzhou University, Yangzhou, P.R. China
4. College of Animal Science and Technology & College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, P.R. China