抄録
Sichuan snub-nosed monkeys are generally seasonal breeders in the wild and in captivity, although copulation can occur throughout the year. Previous studies suggest that estradiol modulates female sexual behavior during the mating season. However, the effects of social context on estrogen levels and behavior have not been fully explored. We studied the relationship between sexual behaviors and fecal estrogen levels in a group of captive Sichuan snub-nosed monkeys in the Everland Zoological Garden, South Korea. The study group contained one adult and subadult male, and two females at the beginning of the study, but group composition changed several times during the study. We compared female behavior and fecal estrogen levels during the mating and non-mating seasons to see how hormone levels differ in different seasons and to assess how hormone levels are related to behavior. We collected behavioral data for six months and collected fecal samples at 2-3-day intervals for four months spanning the mating and non-mating seasons, and analyzed fecal estrogen levels via RIA. We found clear periodic solicitation and copulation peaks by the adult female in the mating season, which corresponded with sharp peaks in fecal estrogens. During the non-mating season, solicitation rates, copulation rates, and fecal estrogens were generally low. However, one non-pregnant female displayed a sharp peak in solicitations, copulations, and estrogens during the non-mating season 10-14 days after a male replacement. Our results provide preliminary evidence that social and behavioral changes affect estrogen levels in Sichuan snub-nosed monkeys.
