[1] Chinese Acad Agr Sci, Inst Anim Sci, Beijing 100193, Peoples R China
[2] NE Forestry Univ, Coll Wildlife Resources, Harbin 150040, Peoples R China
[3] Peoples Liberat Army Gen Hosp, Dept Pathol, Beijing 100853, Peoples R China
[4] Shanxi Agr Univ, Coll Sci & Art, Taigu 030801, Shanxi, Peoples R China