TESTICULAR ACTIVITY IN THE BURROWING FROG TOMOPTERNA-BREVICEPS

The burrowing frog T. breviceps exhibits continuo-discontinuous type spermatogenesis. The gonadosomatic index, diameter of testis, seminiferous tubule and Leydig cell nucleus undergo significant annual variation. Recruitment of differentiated stage 0 cell nests begins in September and were maximum in November. There is inverse correlation between stage 0 and all the other stages (stage I-V) of spermatogenesis. All the stages of spermatogenesis undergo significant seasonal variation. Mitotic and meiotic activity is mainly confined to February-October. It is estimated that a primary spermatogonium gives rise to around 240 spermatozoa. The testicular cycle is divided into breeding phase (April-September), postbreeding phase (October-December) and preparatory phase (January-March). Oocytes are found to occur within and between the seminiferous tubules. Leydig cell and spermatogenetic cycles run parallel.