Abstract
This study aimed to investigate and characterize the spermatogonial stem cells (SSCs) in buffaloes at different stages of development, including prenatal, neonatal, prepubertal, and adult testes. We sought a comprehensive understanding of these cells through a combination of histological, immunohistochemical, and ultrastructural analyses. Specifically, we examined changes in the expression of two potential SSC markers, OCT4 and PGP9.5, using immunohistochemistry. Additionally, we conducted a real-time quantitative polymerase chain reaction (RT-qPCR) to assess the relative gene expression of OCT4 and PGP9.5. The relative expression of the OCT4 gene was down-regulated in the adult testes compared to its expression during prepubertal and neonatal life. The relative expression of the PGP9.5 gene was up-regulated in the neonatal testes and down-regulated in the prepubertal and adult testes. The spermatogonia were round, oval-to-ellipsoidal cells lying over the basement membrane (BM) with a round-to-oval nucleus. Based on the immunoexpression of the putative SSC markers, OCT4 and PGP9.5, we concluded that the proportion of stem cells was highest during the neonatal stage, followed by the prepubertal and prenatal stages. This finding sheds light on the dynamics of spermatogonial stem cells in buffalo testes at different developmental stages, providing valuable insights into these cells' regulation and potential applications.