1. Faculty of Engineering Science, Kansai University, Yamate-cho 3-3-35, Suita, Osaka 564-8680, Japan
2. Kanagawa Institute of Industrial Science and Technology, Shimo-imaizumi 705-1, Ebina, Kanagawa 243-0435, Japan
3. Livestock Industry Technology Station, Hongo 3750, Ebina, Kanagawa 243-0417, Japan
4. School of Veterinary Medicine, Azabu University, Fuchinobe 1-17-71, Chuo, Sagamihara 252-5201, Japan
5. Faculty of Science and Technology, Keio University, Hiyoshi 3-14-1, Kohoku, Yokohama 223-8522, Japan