HORMONES AND MATING BEHAVIOR 



1191 



Tablets of stilbestrol dipropionate or es- 

 tradiol were effective incitants in intact cows 

 and heifers unless a functioning corpus lu- 

 teum was present (Hammond, Jr., and Day, 

 1944). Male-like behavior is displayed at 

 other times than at estrus by cows with 

 ovaries containing cystic follicles or that are 

 otherwise diseased (Pearl and Surface, 1915; 

 Calder, 1927; Fernandez, 1940; Casida, Mc- 

 Shan and Meyer, 1944; Garm, 1949; Way- 

 man and Asdell, 1952), by apparently 

 healthy cows which are not in heat when 

 they are mounted by estrous cows (Weber, 

 1911; Hammond, 1927; de Alba and Asdell, 

 1946; Roark and Herman, 1950), and by an 

 anestrous ewe which had not been brought 

 into heat following treatment with pregnant 

 mare serum and testosterone (Cole, Hart 

 and ]\liller, 1945). On two occasions an an- 

 estrous lioness (female B) performed the 

 gross coital movements of the male after an 

 estrous animal (female A) had forced her- 

 self under B's body (Cooper, 1942). Gass- 

 ner (1952), in contrast to Garm (1949), 

 doubts that nymphomania in cows is a con- 

 sequence of hyperestrogenism; he suggests 

 that it is caused by certain metabolites of 

 an androgenic nature secreted by the ovary 

 or, more likely, by the adrenal cortex. 



The problem is further complicated by re- 

 sults which led Beach and Rasquin (1942) to 

 express doubt that mounting behavior by the 

 female rat is stimulated by ovarian hor- 

 mones. They presented evidence (1) that 

 masculine copulatory reactions are exhibited 

 by intact females with equal frequency at 

 all stages of the estrous cycle, (2) that ovari- 

 ectomy prepuberally or during adulthood 

 eliminated receptive behavior, but had no 

 obvious effect on the execution of the male 

 pattern, and (3) that injection of estrogen 

 and progesterone into spayed females re- 

 vived receptivity without altering masculine 

 behavior. In the same year Beach (1942b) 

 reported that testosterone propionate in- 

 creased the masculine reactions of females 

 95 per cent; consequently, as far as this 

 hormone is concerned, an influence on the 

 display of masculine behavior l)y the female 

 is not questioned. 



As matters stand, the necessity for andro- 

 gens need not be invoked to account for the 

 male-like mounting disi)layed so commonly 



by the female guinea pig. The rat is respon- 

 sive to exogenous androgen but does not re- 

 quire hormones of ovarian origin. The cow 

 requires some hormone of ovarian or adrenal 

 origin, but, in the opinion of Gassner, prob- 

 ably a metabolite of androgenic nature 

 having its origin in the adrenal cortex. Ham- 

 mond, Jr., and Day (1944) found, however, 

 that estrogenic substances were effective 

 stimulants of masculine behavior by cows. 

 Reconciliation of the diverse observations 

 may not be easy, but it should not be im- 

 possible. 



Investigations of running activity have 

 been limited to the rat; consequently, what 

 is said with respect to its hormonal control 

 applies with certainty only to this species. 

 In contrast to the experience when the hor- 

 monal requirements of the mating response 

 were being studied (Boling and Blandau, 

 1939; Beach, 1942a), single injections of es- 

 tradiol benzoate with or without progester- 

 one were ineffective (Young and Fish, 1945) . 

 On the other hand, the addition of human 

 pregnancy urine to the drinking water, daily 

 injections of estrone, or the implantation of 

 pellets of estrone restored activity to a level 

 only slightly below that displayed before 

 ovariectomy (Richter and Hartman, 1934; 

 Young and Fish, 1945). For some reason, 

 when pellets of estrone were implanted the 

 activity tended to be cyclic, even though the 

 amount absorbed from day to day must have 

 been nearly uniform. In a recent personal 

 communication. Dr. Ernst Barany of the 

 Department of Pharmacology, Uppsala, has 

 written that running activity was increased 

 in some spayed female rats when 0.5 fxg. of 

 estradiol benzoate was given in a single in- 

 jection; 5 or 10 fxg. seem to have been more 

 effective. Latency was always about 48 

 hours. Estrone was not more active weight 

 for weight than estradiol. Explanation 

 should be sought for what appear to be 

 contradictory results. 



A consideration of the data bearing on the 

 hormonal regulation of mating behavior in 

 the female suggests the following generaliza- 

 tion. Displa^^ of the three types of estrous 

 behavior, the copulatory response, male-like 

 mounting, and running activity, is induced 

 by the gonadal hormones, and possibly, in 

 the case of running activity in the wild Nor- 



