1. Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
2. United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
3. Equine Research Institute, Japan Racing Association, Tochigi 329-0412, Japan
4. Ritto Training Center, Japan Racing Association, Shiga 520-3085, Japan
5. Hidaka Training and Research Center, Japan Racing Association, Hokkaido 057-0171, Japan
6. Department of Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan
7. Cooperative Division of Veterinary Sciences (Doctoral Program), Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan