1. Faculty of Veterinary Science, Laboratory of Veterinary Surgery, Nippon Veterinary and Life Science University, Tokyo, Japan
2. Faculty of Veterinary Science, Laboratory of Veterinary Internal Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
3. Faculty of Veterinary Science, Laboratory of Small Animal Surgery, School of Veterinary Medicine, Kitasato University, Aomori, Japan
4. Faculty of Veterinary Science, Azabu University Veterinary Teaching Hospital, Kanagawa, Japan