[1] Chinese Acad Sci, State Key Lab Reprod Biol, Inst Zool, Beijing 100101, Peoples R China
[2] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China
[3] INRA, UMR Biol Dev & Reprod 1198, F-78352 Jouy En Josas, France
[4] Ecole Natl Vet Alfort, F-94700 Maisons Alfort, France