Interactive effect of light colours and temporal synergism of circadian neural oscillations in reproductive regulation of Japanese quail

Results indicate that the 8-hr temporal phase relation of neural oscillations suppresses reproductive activity even during the photosensitive phase of the red light exposed quail (R LED + 8-hr) compare to the R LED controls. On the other hand, the 12-hr temporal phase relation stimulates the gonadal development of the B LED + 12-hr quail compared to the B LED controls which after completing one cycle entered into a regressive phase and remained sexually quiescent. These experiments suggest that the temporal phase relations of circadian neural oscillations, in addition to modulating the classical photoperiodic responses, may also modulate the gonadal responses to blue (suppressive) and red (stimulatory) light. These studies led us to conclude that the temporal phase relation of serotonergic and dopaminergic oscillations is not only an important regulator of avian reproduction but may also override the classical effects of light colours in Japanese quail.