1. Department of Microbiology, Sapporo Medical University School of Medicine, Sapporo, Japan.
2. Department of Veterinary Internal Medicine, Tottori University, Tottori, Japan.
3. Laboratory of Food Microbiology and Food Safety, Department of Health and Environmental Sciences, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan.
4. Sanritsu Zelkova Veterinary Laboratory, Kawasaki, Japan.