1. Department of Laboratory Animal Science, Faculty of Agriculture, Tottori University, Tottori 680-8553, Japan
2. Department of Anatomy and Embryology, Ehime University School of Medicine, Toh-on, Ehime 791-0295, Japan
3. Department of Obstetrics and Gynecology, Ehime University School of Medicine, Toh-on, Ehime 791-0295, Japan
4. Department of Veterinary Internal Medicine, Faculty of Agriculture, Tottori University, Tottori 680-8553, Japan
5. Department of Veterinary Biochemistry, Faculty of Agriculture, Tottori University, Tottori 680-8553, Japan