1[1]R.P. Amann and B.D.Schanbacher. Physiology of male reproduction. Jornal of Animal Sience. 57.(2): 380～403
2[2]F.M.Cardoso and H.P.Godinho Daily Sper production of Zebu (Bos Indicus by Quantitative Histology of the Testis.Theriogenology. 1985,23.(6): 841～847
3[3]W.E.Berndtson.Methods for Quantifying Mammalian Spermatogenesis:a Review Journal of Animal Science 1977,44.(5): 818-833
4[4]H.H.Cole and P.T.Cupps Reproduction in Domestic Animals Third Edition Academic Press,New York 1977:212
