1. Joint Faculty of Veterinary Medicine, Kagoshima University , 890-0065 Kagoshima , Japan
2. Kagoshima City Meat Inspection Center , 891-0144 Kagoshima , Japan
3. Department of Surgery, Kyoto University Graduate School of Medicine , 606-8501 Kyoto , Japan
4. Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University , 890-8544 Kagoshima , Japan
5. Department of Food Science and Biotechnology, Faculty of Agriculture, Kagoshima University , 890-0065 Kagoshima , Japan
6. Laboratory of Veterinary Pathology, School of Veterinary Medicine, Kitasato University , 034-0021 Aomori , Japan