1. Faculty of Life and Environmental Science, University of Yamanashi, Yamanashi 400-8510, Japan
2. Laboratory of Animal Reproduction, Graduate School of Veterinary Medicine, Azabu University, Kanagawa 252-0206, Japan
3. School of Veterinary Medicine, Azabu University, Kanagawa 252-0206, Japan
4. Advanced Biotechnology Center, University of Yamanashi, Yamanashi 400-8510, Japan
5. Center for Human and Animal Symbiosis Science, Azabu University, Kanagawa 252-0206, Japan