1. Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
2. Department of Food Science and Human Wellness, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
3. Faculty of Veterinary Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
4. Research Office Concerning the Health of Humans and Birds, Abashiri, Hokkaido 099-3119, Japan