STUDIES ON ESTRUS-INDUCING (PHEROMONAL) ACTION OF MALE DEERMOUSE URINE

Female deermice show estrus infrequently when caged in groups in a male-free environment. Incidence of estrus is increased, in some cases more than twofold, following exposure to the presence of a deermouse male or to his urine. As little as 0.17 ml of urine dripped onto the bedding each day for 3 days was sufficient to give a maximum response among a cage of 10 females. Urine from male laboratory mice did not increase the incidence of estrus among deermouse females. The adult female's response to urine was not affected by the presence or absence of an adult male during her early life. © 1968.