[1] Iowa State Univ, Dept Anim Sci, Ames, IA 50011 USA
[2] Iowa State Univ, Ctr Integrated Anim Genom, Ames, IA 50011 USA
[3] Huazhong Agr Univ, Minist Educ, Key Lab Agr Anim Genet Breeding & Reprod, Wuhan, Peoples R China
[4] Huazhong Agr Univ, Coll Anim Sci & Technol, Wuhan, Peoples R China