Histological examination of testicular cell development and apoptosis in the ostrich chick

Th e aim of this study was to observe the microstructure and ultrastructure of the testis, demonstrate testicular cell development and apoptosis, and elucidate regularity of development and apoptosis in ostrich chick testes. By employing light microscopy 3 obvious development characteristics were detected with ostrich age increasing: fi rst, many primordial germ cells and a few spermatogonia were found while seminiferous tubule integrity was not evident in testes of 1-day-old ostrich chicks nor were primordial germ cells. In the 30-day-old ostrich chicks spermatogonia were completely diff erentiated, but very few primary spermatocytes were observed in testes at 45 days of age. Second, the quantity of mitochondria in spermatogonia and lipid droplet in Leydig cells increased gradually with the increasing age of astrish. Th ird, testicular cell apoptosis was observed and the number of apoptotic testicular cells showed a peak in the testis of 45-day-old ostrich chicks (P < 0.05), as testicular cells were prone to apoptosis at that age.