Changes in Fecal Estrogen Levels and Sexual Behavior in Captive Sichuan Snub‐Nosed Monkeys (Rhinopithecus roxellana) Following a Male Replacement

Abstract

Rhinopithecus roxellana are generally seasonal breeders, 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 estrogens in a group of captive R. roxellana during a period of social instability. We collected behavioral data for six months and collected fecal samples at 2-3-day intervals for four months spanning the mating and nonmating seasons, and analyzed fecal estrogen levels via RIA. Females showed clear cyclic solicitation and copulation peaks in the mating season, which corresponded with sharp peaks in fecal estrogens. During the nonmating season, solicitation rates, copulation rates, and fecal estrogens were generally low. However, one nonpregnant female displayed a sharp peak in solicitations, copulations, and estrogens during the nonmating season 10-14 days after a male replacement. Our results provide preliminary evidence that social and behavioral changes affect estrogen levels in R. roxellana.

Production Efficiency, Nutrient Utilization and Intestinal Histology of Broilers Fed on Energy Diluted Diet Supplemented with Lipase and Bile Acids

“…For adult macaques, mating season is a particularly challenging period with several conspecific spouse competition in a polygamous society. In order to cope with the increased physical and energetic demands of conspecific competition in mating period, males often increased food intake, sexual dimorphism, and a marked rise in testosterone and glucocorticoid levels (Romero, 2002;Girard-Buttoz et al, 2009), and females showed clear cyclic solicitation and copulation peaks (Kim et al, 2013). As strict seasonal breeder, adult Taihangshan macaques usually mate from September to December annually (Lu et al, 2009;Tian et al, 2013;Guo et al, 2020), with increased mating rates and aggressive behaviors in both sexes (Sun, 2019), which reasonably explained the higher cortisol levels during this period.…”

Production Efficiency, Nutrient Utilization and Intestinal Histology of Broilers Fed on Energy Diluted Diet Supplemented with Lipase and Bile Acids

“…For adult macaques, mating season is a particularly challenging period with several conspecific spouse competition in a polygamous society. In order to cope with the increased physical and energetic demands of conspecific competition in mating period, males often increased food intake, sexual dimorphism, and a marked rise in testosterone and glucocorticoid levels (Romero, 2002;Girard-Buttoz et al, 2009), and females showed clear cyclic solicitation and copulation peaks (Kim et al, 2013). As strict seasonal breeder, adult Taihangshan macaques usually mate from September to December annually (Lu et al, 2009;Tian et al, 2013;Guo et al, 2020), with increased mating rates and aggressive behaviors in both sexes (Sun, 2019), which reasonably explained the higher cortisol levels during this period.…”

Morphological Analysis of the Axonal Projections of EGFP-Labeled Esr1-Expressing Neurons in Transgenic Female Medaka

“…For example, most vertebrates show species-specific courtship behavior only after sexual maturation and during the breeding season. Thus, hormonal signals from the gonads have been suggested to control neural circuits for the modulation of sexual behaviors (18,19). However, the nature of such estrogen-sensitive neurons remains to be elucidated.…”

Production Efficiency, Nutrient Utilization and Intestinal Histology of Broilers Fed on Energy Diluted Diet Supplemented with Lipase and Bile Acids

“…For adult macaques, mating season is a particularly challenging period with several conspecific spouse competition in a polygamous society. In order to cope with the increased physical and energetic demands of conspecific competition in mating period, males often increased food intake, sexual dimorphism, and a marked rise in testosterone and glucocorticoid levels (Romero, 2002;Girard-Buttoz et al, 2009), and females showed clear cyclic solicitation and copulation peaks (Kim et al, 2013). As strict seasonal breeder, adult Taihangshan macaques usually mate from September to December annually (Lu et al, 2009;Tian et al, 2013;Guo et al, 2020), with increased mating rates and aggressive behaviors in both sexes (Sun, 2019), which reasonably explained the higher cortisol levels during this period.…”

Morphological Analysis of the Axonal Projections of EGFP-Labeled Esr1-Expressing Neurons in Transgenic Female Medaka

“…For example, most vertebrates show species-specific courtship behavior only after sexual maturation and during the breeding season. Thus, hormonal signals from the gonads have been suggested to control neural circuits for the modulation of sexual behaviors (18,19). However, the nature of such estrogen-sensitive neurons remains to be elucidated.…”

Production Efficiency, Nutrient Utilization and Intestinal Histology of Broilers Fed on Energy Diluted Diet Supplemented with Lipase and Bile Acids

“…For adult macaques, mating season is a particularly challenging period with several conspecific spouse competition in a polygamous society. In order to cope with the increased physical and energetic demands of conspecific competition in mating period, males often increased food intake, sexual dimorphism, and a marked rise in testosterone and glucocorticoid levels (Romero, 2002;Girard-Buttoz et al, 2009), and females showed clear cyclic solicitation and copulation peaks (Kim et al, 2013). As strict seasonal breeder, adult Taihangshan macaques usually mate from September to December annually (Lu et al, 2009;Tian et al, 2013;Guo et al, 2020), with increased mating rates and aggressive behaviors in both sexes (Sun, 2019), which reasonably explained the higher cortisol levels during this period.…”

Morphological Analysis of the Axonal Projections of EGFP-Labeled Esr1-Expressing Neurons in Transgenic Female Medaka

“…For example, most vertebrates show species-specific courtship behavior only after sexual maturation and during the breeding season. Thus, hormonal signals from the gonads have been suggested to control neural circuits for the modulation of sexual behaviors (18,19). However, the nature of such estrogen-sensitive neurons remains to be elucidated.…”