[1] Huazhong Agr Univ, Coll Vet Med, Dept Clin Vet Med, Wuhan 430070, Peoples R China
[2] Univ Agr Faisalabad, Fac Vet Sci, Dept Anat & Histol, Faisalabad 38000, Punjab, Pakistan
[3] Chinese Acad Agr Sci, Inst Anim Sci, Embryo Biotechnol & Reprod Lab, Beijing 100193, Peoples R China
[4] Univ Agr Faisalabad, Fac Vet Sci, Dept Theriogenol, Faisalabad 38000, Punjab, Pakistan