1. Laboratory of Veterinary Anatomy, Faculty of Agriculture, Iwate University, Morioka, Iwate 020–8550, Japan
2. Department of Basic Veterinary Science, The United Graduate School of Veterinary Science, Gifu University, Gifu, Gifu 501–1193, Japan
3. Department of Applied Veterinary Science, The United Graduate School of Veterinary Science, Gifu University, Gifu, Gifu 501–1193, Japan
4. Center for Regional Collaboration in Research and Education, Iwate University, Morioka, Iwate 020–8550, Japan