Parviz Tajik - Department of Theriogenology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
Negar Damghanian - Department of Clinical sciences, Faculty of Veterinary Medicine, Semnan University, Semnan, Iran
Rahele Reza - Department of Clinical sciences, Faculty of Veterinary Medicine, Semnan University, Semnan, Iran
Reza Narenji Sani - Department of Clinical sciences, Faculty of Veterinary Medicine, Semnan University, Semnan, Iran

Background: The complex process of spermatogenesis is regulated by various factors. Studies on spermatogonial stem cells (SCCs) have provided very important tool to improve herd genetic and different field. 0.2 to 0.3 percent of total cells of seminiferous tubules consist of spermatogonial stem cells.Methods: To investigate and biomanipulation of these cells, proliferation and viability rate of cells should be increased in vitro, at first. Human chorionic gonadotropin (hCG) has been suggested to play a determinant role to increase spermatogenesis in cow. The identity of the Sertoli cells and spermatogonial stem cells were confirmed through immunocytochemistry and colony morphology, respectively. Co-cultured Sertoli and spermatogonial cells were treated with hCG in different doses of 2, 5 and 10 IU mL-1 hCG, before colony assay. In this study, the in vitro effects of hCG on spermatogonial cell colony formation were investigated. Sertoli and spermatogonial cells were isolated from 3-5 months old calves.Result: hCG increased in vitro proliferation of spermatogonial cells in comparison with control group.Conclusion: Using hCG provided proper bovine spermatogonial stem cell culture medium for long time in in vitro study of these cells.

Human chorionic gonadotropin, Sertoli cells, Bovine spermatogonial stem cells