1. Department of Veterinary Surgery, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Korea.
2. Guardian Angel Veterinary Hospital, Anyang 14112, Korea.
3. Chungnam National University Sejong Hospital, Sejong 30099, Korea.
4. Department of Cardiothoracic Surgery, Chungnam National University Hospital, College of Medicine, Chungnam National University, Daejeon 35015, Korea.