1. Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology; Institute of Subtropical Agriculture; The Chinese Academy of Sciences; Changsha Hunan P. R. China
2. University of the Chinese Academy of Sciences; Beijing China
3. Department of Animal Science; University of Florida; Gainesville FL USA
4. Department of Animal Science; Texas A&M University; TAMU TX USA
5. Chongqing Key Laboratory of Forage and Herbivorce; College of Animal Science and Technology; Southwest University; Chongqing China