BEHAVIORAL-RESPONSES TO SEX STEROIDS OF GONADECTOMIZED AND SEXUALLY REGRESSED QUAIL

The behavioral and morphological effects of exogenous sex hormones in gonadectomized quail (Coturnix coturnix japonica) was compared with those in quail having regressed gonads as a result of exposure to short days. Male quail were assigned to 1 of 3 treatment groups: intact, exposed to 16 h light:8 h darkness and injected with oil (group 16L); gonadectomized, exposed to 16 h light:8 h darkness and injected with 2.5 mg testosterone propionate (TP)/day (group 16L-castrated); and intact, exposed to 8 h light:16 h darkness, and injected with 2.5 mg TP/day (group 8L). Groups 16L-castrated and 8L responded similarly to testosterone, copulating with equal frequency and rapidity after the same number of days of treatment, and also developing proctodeal (foam) glands of a similar size. Only on day 7 of testosterone treatment did the results for these 2 groups differ. By day 14, the behavior of both groups resembled that of the 16L birds. Female quail were assigned to the same 3 treatment groups, except that the hormone treatment was 25 .mu.g estradiol benzoate/day. Group 8L became sexually receptive sooner than the 16L-ovariectomized quail, but by day 13 both groups had oviducts of similar size, were equally receptive, and were as receptive as the 16L females. The effects of photoperiod on sexual behavior in this species are mediated largely, if not wholly, by the gonads. Exposure to short day and surgical gonadectomy are rather similar experimental procedures in the quail.