1. College of Veterinary Medicine and Veterinary Medical Research Institute, Jeju National University, Jeju 63243, Korea.
2. Department of Anatomy, Kosin University College of Medicine, Busan 49267, Korea.
3. Functional Biomaterials Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Korea.
4. Department of Animal Science, College of Life Science, Sangji University, Wonju 26339, Korea.
5. Department of Veterinary Anatomy and Animal Behavior, College of Veterinary Medicine and BK21 FOUR Program, Chonnam National University, Gwangju 61186, Korea.
6. Scleroprotein and Leather Research Institute, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
7. Laboratory of Comparative Animal Medicine, Division of Animal Life Science, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.