1. Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 5200 Kihara-Kiyotake-cho, Miyazaki 889-1692, Japan
2. Miyakonojo Meat Inspection Center, 38-1 Hirae-cho, Miyakonojo-shi, Miyazaki 885-0021, Japan
3. Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
4. Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan