1. School of Veterinary Nursing and Technology, Faculty of Veterinary Science; Nippon Veterinary and Life Science University; Tokyo Japan
2. Department of Veterinary Pathology, Faculty of Veterinary Science; Nippon Veterinary and Life Science University; Tokyo Japan
3. Department of Veterinary Clinical Pathology, Faculty of Veterinary Science; Nippon Veterinary and Life Science University; Tokyo Japan
4. Department of Reproduction, Faculty of Veterinary Science; Nippon Veterinary and Life Science University; Tokyo Japan
5. Department of Urology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences; Okayama University; Okayama Japan