Annual reproductive cycle of male rohu, Labeo rohita (Ham.), in Tarai region of Uttaranchal

Abstract

Testicular development of Labeo rohita under ambient environmental conditions in Tarai region of Uttaranchal was associated with increasing day-length and temperature, whereas testicular maturity and spermiogenesis during spawning phase seem to be correlated with the lowering of water temperature, attributable to rainfall. The primary spermatogonial cells and spermatocytes, a few lobules with spermatozoa and spermatids were observed in preparatory phase. The peak of spermatogenesis having active interstitial Leydig cells was recorded during pre-spawning phase. During spawning phase, most of the testicular lobules were packed with sperm masses alongwith a few secondary spermatocytes and spermatids. Decreased interlobular space with some inactive interstitial cells was noticed during post-spawning phase. The histological changes in liver showing augmented biosynthetic activities corresponded with testicular growth and maturation and changes in hepatopancreatic cells were suggestive of energy mobilization