1. College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, P.R. China;
2. Guangxi Zhuang Autonomous Region Terrestrial Wildlife Medical-aid and Monitoring Epidemic Diseases Research Center, Nanning, P.R. China;
3. Department of Infection Management and Disease Control, Chinese PLA General Hospital, Beijing, P.R. China;
4. Manzhouli Customs District, Manzhouli, P.R. China