Effect of photoperiod upon age and maintenance of sexual development in female Coturnix coturnix japonica

Gary S. Stein, University of Massachusetts Medical School
W. L. Bacon, University of Ohio


Coturnix kept in a 14L:10D photoperiod from hatch began to lay their first eggs at a mean age of 42.8 days (range 38-55). Approximately 2/3 of Coturnix held from hatch in photoperiods of 6L:16D light were laying at 165 days of age. Mean age at first egg was 112.7 days (range 68-162 days) in 8L:16D and 130.8 days (range 117-158 days) in 6L:18D photoperiod. Coturnix transferred from a non-stimulatory (8L:16D) photoperiod to a stimulatory one (14L:10D or 24L) begun laying in 15-20 days if less than 140 days old, and in about 5 days if greater than 140 days old, when trasferred. Birds which has spontaneously begun to lay in an 8L:16D photoperiod did not stop laying when the photoperiod was reduced to 6L:18D. Those which began laying under 14L:10D photoperiod ceased laying in about 15 days if 89 or fewer days old when switched to 8L:16D, or in about 6 days if 140 or more days old. Those switched from 14L:10D to 6L:18D ceased laying in about 13 days when 76 days old, and 7 days when 89 days old.