Effects of constant photoperiod-temperature regimes on testes and pituitary gonadotropic cells of the murrel, Channa punctatus (Bloch) during the annual reproductive cycle.

Mal Channa punctatus were maintained under constant photoperiod-warm temperature regimes (LD 16:8 and LD 8:16 at 30 degrees C) for one year. LD 16:8 regime stimulates testicular maturation and the activity of gonadotropic cells whereas LD 8:16 regime inhibits testicular maturation and also activity of gonadotropic cells. These results indicate a close correlation between the activity of gonadotropic cells and testes under long and short photoperiods at 30 degrees C regimes.