1. Department of Applied Veterinary Science; Obihiro Hokkaido 080-8555 Japan
2. Laboratory of Food Microbiology & Immunology, Research Center for Animal Hygiene and Food Safety; Obihiro University of Agriculture and Veterinary Medicine; Obihiro Hokkaido 080-8555 Japan
3. Laboratory of Bacteriology and Infectious Diseases, Immunological Research Center; Institute of Veterinary Medicine; Ulaanbaatar 210153 Mongolia