1. Department of Basic Veterinary Medicine; College of Animal Science and Veterinary Medicine; Shandong Agricultural University; Shandong China
2. Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention; Shandong Agricultural University; Shandong China
3. Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention; Shandong Agricultural University; Shandong China
4. Department of Preventive Veterinary Medicine; College of Animal Science and Veterinary Medicine; Shandong Agricultural University; Shandong China