Effects of prepubertal ovariectomy on the development of scent glands, scent marking, and aggressive behaviors of female tamarin monkeys (Saguinus fuscicollis)

The effects of prepubertal ovariectomy on scent gland development, scent marking behavior, and on social interactions with strange adult conspecifics were studied in adult females cohabiting with intact males. Eight females were ovariectomized and eight underwent control surgery at 6 months of age. All were returned to their families after surgery and allowed to reach sexual maturity. At 18 months of age, each female was permanently paired with an adult, intact male. When the subjects were 21 months old, the social interactions of all pairs with strange adults were tested in a situation analogous to a territorial encounter. The scent marking activities of the subjects and their mates were studied during “territorial encounters,” in trial-free control situations, and in the presence of novel objects. Ovariectomy prior to puberty retarded the development of the scent gland but did not inhibit it completely. Social interactions with strange conspecifics were also affected. Ovariectomized females showed fewer threat displays than did control females, but there was no significant difference in the amount of injurious aggression both female groups directed at the strangers. Under all testing conditions, ovariectomized females tended to scent mark less frequently with the circumgenital-suprapubic gland than did controls. This difference was statistically significant only under some of the testing conditions. Intact females scent marked more frequently than their males but ovariectomized females did so only under trial-free testing conditions. The sternal scent gland was used very infrequently by all subjects and there was no difference in marking activity between males and females or between ovariectomized and control females.