Abstract
Captive-born squirrel monkeys of three different subtypes (Colombian, Bolivian, Peruvian), ranging in age from 1 to 4.5 years for males and 1 to 3.5 years for females, were examined at 3-month intervals throughout the year for seasonal changes in levels of plasma testosterone and progesterone and in body weight. Cyclical activity of testosterone in males began between 2 and 3 years of age but became more defined by the time the animals were 3–4 years old. Peak values occurred in February and May and corresponded to the the time of year in which adults normally mate. Elevations of progesterone occurred initially at approximately 2.5 years of age in February and May, and mainly infernales of the Colombian subtype. However,unlike levels of testosterone in males of this age, which declined in August and November (following the typical breeding season), levels of progesterone in females continued to increase during these months. Seasonal changes in body weight were also found in males but these changes were less evident than, and did not correlate with, hormonal changes.
Similar content being viewed by others
References
Ausman, L. M., Gallina, D. L., Hayes, K. C., and Hegsted, S. M. (1976). Hematological development of the infant squirrel monkey (Saimiri sciureus).Folia Primatol. 26: 292–300.
Baldwin, J. D. (1969). The ontogeny of social behaviour of squirrel monkeys (Saimiri sciureus) in a seminatural environment.Folia Primatol. 11: 35–79.
DuMond, F. V. (1968). The squirrel monkey in a seminatural environment. In Rosenblum, L. A., and Cooper, R. W. (eds.),The Squirrel Monkey, Academic Press, New York, pp. 88–146.
Frankel, A. I., Mock, E. J., Wright, W. W., and Kamel, F. (1975). Characterization and physiological validation of radioimmunoassay for plasma testosterone in the male rat.Steroids 25: 73–98.
Gibori, G., Antczak, E., and Rothchild, I. (1977). The role of estrogen in the regulation of luteal phase progesterone secretion in the rat after day 12 of pregnancy.Endocrinology 100: 1483–1495.
Glick, B. B. (1979). Testicular size, testosterone level, and body weight in maleMacaca radiata: Maturation and seasonal effects.Folia Primatot. 32: 268–289.
Kaack, B., Brizzee, K. R., and Walker, L. (1979a). Some biochemical blood parameters in the developing squirrel monkey.Folia Primatol. 32: 309–317.
Kaack, B., Walker, L., and Brizzee, K. R. (1979b). The growth and development of the squirrel monkey (Saimiri sciureus)Growth 43. 116–135.
Kaplan, J. N. (1977). Breeding and rearing squirrel monkeys (Saimiri sciureus) in captivity.Lab. Anim. Sci. 27: 557–567.
Kaplan, J. N. (1979). Growth and development of infant squirrel monkeys during the first six months of life. In Ruppenthal, G. C., and Reese, D. J. (eds.),Nursery Care of Nonhuman Primates, Plenum, New York, pp. 153–164.
Long, J. O., and Cooper, R. W. (1968). Physical growth and dental eruption in captive-bred squirrel monkeys,Saimiri sciureus (Leticia, Columbia). In Rosenblum, and Cooper, R. W. (eds.),The Squirrel Monkey, Academic Press, New York, pp. 193–205.
Mendoza, S. P., Lowe, E. L., Davidson, J. M., and Levine, S. (1978a). Annual cyclicity in the squirrel monkey (Saimiri sciureus): The relationship between testosterone, fatting, and sexual behavior.Horm. Behav. 11: 295–303.
Mendoza, S. P., Lowe, E. L., Resko, J. A., and Levine, S. (1978b). Seasonal variations in gonadal hormones and social behavior in squirrel monkeys.Physiol. Behav. 20: 515–522.
Rose, R. M., Bernstein, I. S., Thomas, P., Gordon, M. A., and Lindsley, J. G. (1978). Changes in testosterone and behavior during adolescence in the male rhesus monkey.Psychosom. Med. 40: 60–70.
Rosenblum, L. A. (1968). Mother-infant relations and early behavioral development in the squirrel monkey. In Rosenblum, L. A., and Cooper, R. W. (eds.),The Squirrel Monkey, Academic Press, New York, pp. 207–233.
Rosenblum, L. A. (1972). Reproduction of squirrel monkeys in the laboratory. In Beveridge, W. I. B. (ed.),Breeding Primates, Karger, New York, pp. 130–143.
Wolf, R. C., O’Connor, R. F., and Robinson, J. A. (1977). Cyclic changes in plasma progestins and estrogens in squirrel monkeys.Biol. Reprod. 17: 228–231.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kaplan, J.N., Chen, J., Smith, E. et al. The development of seasonal variation in gonadal hormones and body weight in the maturing squirrel monkey. Int J Primatol 2, 369–380 (1981). https://doi.org/10.1007/BF02693485
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF02693485