1. Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
2. Biofermin Kobe Research Institute, Biofermin Pharmaceutical Co. Ltd., 7-3-4 Ibukidai-Higashimachi, Nishi-ku, Kobe 651-2242, Japan