1. Department of Veterinary Anatomy, College of Bioresource Sciences
2. Department of Veterinary Surgery, College of Bioresource Sciences
3. Nihon University, Fujisawa, Japan; Division of Companion Animal Surgery, Veterinary Teaching Hospital, Faculty of Agriculture, Iwate University, Morioka, Japan
4. Center for Food Science and Wellness, Gunma University, Maebashi, Japan
5. Department of Biotechnology, Faculty of Bioresource Sciences, Akita Prefectural University, Akita, Japan