1. Everlasting Nature of Asia (ELNA), Ogasawara Marine Center, Ogasawara, Tokyo 100-2101, Japan
2. Laboratory of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
3. Laboratory of Toxicology, Obihiro University of Agricultural and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
4. Research Center for Global Agromedicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
5. Department of Reproductive Immunology and Pathology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn 10-748, Poland