1. The Institute of Biological Resources, Okinawa, Japan
2. Laboratory of Veterinary Pathology, Department of Veterinary, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
3. Equine Research Institute, Japan Racing Association, Tochigi, Japan
4. National Institute of Advanced Science and Technology (AIST), Osaka, Japan
5. Division of Microbiology, Nihon University School of Medicine, Tokyo, Japan