Induction of sexual receptivity in the female broad-headed skink, Eumeces laticeps, by estradiol-17 beta.
Sexual receptivity in the female scincid lizard Eumeces laticeps occurs naturally only during the spring breeding season, which is also when maximal follicular development occurs. The presumption that high estrogen levels are coincidentally present and the need for a reliable method of inducing sexual receptivity for behavioral studies prompted tests of the hypothesis that estrogen induces sexual behavior. A series of experiments established that estradiol-17 beta induces sexual behavior. A series of experiments established that estradiol-17 beta induces sexual receptivity within 4 days when injected every other day at 2.0 micrograms in 20 microliters peanut oil in intact or ovariectomized females. In behavioral tests conducted during August, all control females (intact or ovariectomized injected with vehicle only) rejected courtship whereas all females receiving estrogen copulated. Estrogen injections also induced a statistically significant change from rejection to receptivity within individuals. Initial attempts to implant estradiol-17 beta in Silastic tubes killed all females so treated.
D000818:Animals; D002214:Capsules; D004343:Drug Implants; D004958:Estradiol / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D008116:Lizards / Q000502:physiology*; D010052:Ovariectomy; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D012826:Silicone Elastomers; D013045:Species Specificity; D013268:Stimulation, Chemical
D002214:Capsules; D004343:Drug Implants; D012826:Silicone Elastomers; D004958:Estradiol