1. Laboratory of Veterinary Internal Medicine, Graduate School of Veterinary Medicine, Hokkaido University, N18 W9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
2. Veterinary Teaching Hospital, Graduate School of Veterinary Medicine, Hokkaido University, N18 W9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
3. Coriell Institute for Medical Research, 403 Haddon Ave, Camden, NJ 08103, USA
4. Laboratory of Comparative Pathology, Graduate School of Veterinary Medicine, Hokkaido University, N18 W9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
5. North Lab, Hokkaido, Hondori 2-chome, Kita 8-35, Shiroishi-ku, Sapporo, Hokkaido 003-0027, Japan