1. Department of Poultry Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China (Zhang, Bao, Yu, Cheng, Tan, Qiu, Song, Ding)
2. College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu, China (Zhang, Fei)
3. Poultry Institute, Chinese Academy of Agricultural Sciences, Yangzhou, Jiangsu, China (Dai)