1. Graduate Institute of Veterinary Medicine, National Taiwan University, Taipei 106, Taiwan
2. School of Medicine, Chung Shan Medical University, Taichung 402, Taiwan
3. Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
4. Department of Veterinary Medicine, National Chiayi University, Chiayi 600, Taiwan
5. Department of Post-Baccalaureate Veterinary Medicine, Asia University, Taichung 413, Taiwan