1. Division of Infectious Animal Disease Research, National Institute of Animal Health, National Agriculture and Food Research Organization, Ibaraki, Japan
2. The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
3. Joint Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
4. Department of Animal Disease Control and Prevention, National Institute of Animal Health, National Agriculture and Food Research Organization, Ibaraki, Japan
5. Research and Business Promotion Division, Research Institute for Animal Science in Biochemistry and Toxicology, Kanagawa, Japan