1. Department of Bioscience and Food Production Science, Interdisciplinary Graduate School of Science and Technology, Shinshu University, 8304 Minami-minowa, Kami-ina, Nagano 399–4598, Japan
2. Laboratory of Animal Functional Anatomy (LAFA), Faculty of Agriculture, Shinshu University, Minami-minowa 8304, Kami-ina, Nagano 399–4598, Japan
3. Department of Food Production Science, Graduate School of Agriculture, Shinshu University, 8304 Minami-minowa, Kami-ina, Nagano 399–4598, Japan