1. Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
2. Laboratory of Veterinary Microbiology, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
3. Gifu Prefectural Chuo Livestock Hygiene Service Center, Gifu, Japan
4. United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan