1. Department of Veterinary Clinical Sciences, Jockey Club College of Veterinary and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
2. Centre for Animal Health and Welfare, City University of Hong Kong, Hong Kong SAR, China
3. Storr Liver Centre, Westmead Clinical School and Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
4. Sydney Infectious Diseases Institute, University of Sydney at Westmead Hospital, Westmead, NSW 2145, Australia
5. Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, 4206 Vet Med 3A, Davis, CA 95616, USA
6. Gastrointestinal Laboratory, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
7. College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA