[Effect of continuous illumination on the reproductive function in rats. Aftereffects]

The continuous illumination of 2 months old Wistar rats during 1,2 and 6 months resulted in the appearance of permanent oestrus in 24, 61 and 100% of animals, resp. The weight of newborn rats from the females illuminated during pregnancy was by 7% higher than in the control. The continuous illumination during 1 month prior to mating did not affect the embryogenesis. The weight of 20 days old rats from the females illuminated during 1 month (prior to mating), 2 months (prior to mating + + pregnancy) and 6 months exceeded that of the control ones by 5, 18 and 30%, resp. The increase in the weight of rats persisted in the next reproductive cycle in spite of the standard conditions of light regime (14 hrs day: 10 hrs night).