[Hou, De-Xing;Kumamoto, Takuma;Ishida, Hisako;Hisanaga, Ayami] Kagoshima Univ, Fac Agr, Dept Biochem Sci & Technol, Kagoshima 890, Japan.^[Hou, De-Xing] Hunan Agr Univ, Educ Minist, Engn Res Ctr Feed Safety & Efficient Utilizat, Changsha, Hunan, Peoples R China.