1. Department of Veterinary Microbiology, School of Veterinary Medicine, Azabu University, 1-17-71, Fuchinobe, Sagamiharashi, Kanagawa-Ken 229, Japan
2. Department of Environmental Microbiology, College of Environmental Health, Azabu University, 1-17-71, Fuchinobe, Sagamiharashi, Kanagawa-Ken 229, Japan