1. School of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyounan-chou, Musashino-shi, Tokyo 180-8602, Japan
2. Laboratory of Clinical Pathology, Department of Veterinary Clinical Sciences, Faculty of Agriculture, Kagoshima University, 1-21-24 Kohrimoto, Kagoshima 890-0065, Japan
3. Laboratory of Internal Medicine, Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo 060-0818, Japan