1. Clinical Science and Pathobiology Division; Equine Research Institute; Japan Racing Association; 321-4 Tokami-cho, Utsunomiya-shi Tochigi 320-0856 Japan
2. Ritto Trainig Center; Japan Racing Association; 1028 Misono, Ritto-shi Shiga 520-3085 Japan
3. Miho Trainig Center; Japan Racing Association; Miho-mura, Inashiki-gun Ibaraki 300-0415 Japan
4. Department of Veterinary Clinical Science; Obihiro University of Agriculture and Veterinary Medicine; 2-11, Inada, Obihiro Hokkaido 080-8555 Japan
5. Clinical research department; Nutritional Science Institute; Morinaga Milk Industry Co., Ltd.; 1-83 Higashihara 5-chome, Zama-shi Kanagawa 252-8583 Japan