1. Faculty of Fisheries, Hokkaido University, 3-1-1 Minato, Hakodate 041-8611, Japan, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan, and Central Food Technological Research Institute, Mysore, India 570020