1. College of Animal Science and Technology; Jilin Agricultural University; Changchun 130118 P.R. China
2. Key Laboratory of Animal Nutrition and Feed Science, Jilin Province; Jilin Agricultural University; Changchun 130118 P.R. China
3. Department of Animal Science and Technology, College of Animal Bioscience & Technology; Konkuk University; Seoul 143-701 South Korea
4. Laboratory of Animal Cell Biotechnology, Department of Agricultural Biotechnology; Seoul National University; Seoul 157-921 South Korea
5. Research and Technology Center; Cargill Agri Purina; Seongnam 463-808 South Korea
6. Department of Animal Science, College of Natural Resources and Life Science; Pusan National University; Miryang 627-706 South Korea
7. Department of Animal Science and Biotechnology; Kyungpook National University; Sangju 742-711 South Korea
8. Department of Animal Science; Chungbuk National University; Cheongju Chungbuk 361-763 South Korea