1. a National Institute of Livestock and Grassland Science , Nishinasuno-machi, Nasu-gun, Tochigi , 329-2793 , Japan
2. d Graduate School of Agriculture , Kyoto Prefectural University , Sakyo-ku, Kyoto , 606-8522 , Japan
3. b Environmental Harmonization Department , KANSAI Environmental Engineering Center Co. Ltd. , Chuo-ku, Osaka , 541-0052 , Japan
4. c Technical Research Center , The Kansai Electric Power Co. Inc. , Amagasaki , 661-0974 , Japan