1. Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei 430070, PRChina
2. Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, PRChina
3. State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, PRChina
4. Department of Public Health Sciences, University of Hawaii, Manoa, HI 96822, USA