Histological and histochemical studies on the testicular cycle of a fresh water teleost Channa gachua (Hamilton).

The male reproductive cycle of Channa gachua from fresh water tanks around Dharwad (North 15 degrees 27' latitude, East 75 degrees 01' longitude) is investigated by a) recording the gonosomatic index, every month, over a period 2 consecutive years and b) studying the histological structure of the testis during this period. Based on this study, the fish is suggested to breed twice in a year. The 1st breeding phase coincides with the South-West monsoons and the 2nd with the convectional rains in the month of March. Though C. gachua shows 2 breeding periods, the spermatogenic activity is a continuous process in this fish. The presence of delta 5-3 beta-hydroxysteroid dehydrogenase (delta 5-3 beta-HSDH) and Glucose-6-phosphate dehydrogenase (G-6-PDH) is demonstrated in the interstitial tissue which indicates its steroidogenic potential.