1. College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province 510642, People's Republic of China
2. Guangdong Provincial Key Laboratory of Prevention and Control for Severe Clinical Animal Diseases, Guangzhou, Guangdong Province 510642, People's Republic of China
3. Guangdong Provincial Pet Engineering Technology Research Center, Guangzhou, Guangdong Province 510642, People's Republic of China