1. Division of Therapeutic Science 1, Department of Veterinary Clinical Medicine, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 184-8602, Japan
2. Faculty of Veterinary Medicine, Okayama University of Science, 1-3 Ikoinooka, Imabari-shi, Ehime 794-8555, Japan