1. Department of Animal Sciences, Teikyo University of Science, Tokyo West Campus, 2525 Yatsusawa, Uenohara City 409-0193, Japan
2. Department of Animal Sciences, Teikyo University of Science, Senju Campus, 2-2-1 Senju Sakuragi, Adachi-ku, Tokyo 120-0045, Japan
3. Adachi Park of Living Thing, 2-17-1 Hokima, Adachi-ku, Tokyo 121-0064, Japan