Social and reproductive influences on plasma cortisol in female marmoset monkeys

Different ovarian responses to potential mates underlie species-specific breeding strategies in common marmoset and Goeldi's monkey

“…The only female that showed an increase in cortisol during the Trio condition was the female with a prolonged period of ovarian inactivity, possibly indicating that this infertility was stress-induced. On the other hand, it is possible that the decline in cortisol concentrations exhibited by the majority of females was due to the decline in E1C, given the evidence for other callitrichids that oestrogen activity promotes cortisol secretion (Saltzman et al, 1994b;Ziegler and Sousa, 2002;Ziegler et al, 1995). However, in the current study, Goeldi's monkey cortisol concentrations remained low also after the females started cycling again.…”

“…In most cooperative breeding mammals studied so far, dominant individuals have elevated glucocorticoid levels more often than subordinates, meaning that reproductive inhibition is not mediated by chronic glucocorticoid elevation (Creel, 2001;common marmoset: Abbott et al, 1997;Saltzman et al, 1994bsuricate: Carlson et al, 2004;African wild dog: Creel et al, 1997;naked mole-rat: Faulkes and Abbott, 1997). Social inhibition of reproductive hormones and direct effects of social subordination appear to contribute to this suppression of cortisol synthesis/secretion Saltzman et al, 1994bSaltzman et al, , 1996Saltzman et al, , 1998. In common marmosets as well as in other cooperatively breeding mammals, the inhibition of ovulation seems to be mediated by a specific neuroendocrine mechanism Damaraland mole-rat: Bennett et al, 1996; naked mole-rat: Faulkes et al, 1990).…”

Gender and gonadal status differences in zona reticularis expression in marmoset monkey adrenals: Cytochrome b5 localization with respect to cytochrome P450 17,20-lyase activity

“…Dominance hierarchies in such groups are usually established within 1-2 weeks and may remain stable for several years or more . Characterization of dominant and subordinate status, based on directionality of submissive behavior (Saltzman et al 1996), was confirmed by the occurrence of ovulatory cycles in dominant females and anovulation in subordinate females, based on plasma progesterone levels in blood samples collected twice weekly (Saltzman et al 1994). Subordinates had not ovulated for at least 15 weeks prior to data collection and had not exhibited elevated plasma progesterone concentrations (>10 ng/ml), characteristic of the luteal phase of the ovarian cycle, for at least 60 days.…”

“…Reproductive suppression in subordinate males is mediated largely by inhibition of sexual behavior (Abbott 1993, Baker et al 1999, whereas subordinate females become anovulatory and hypoestrogenemic in response to social cues (Abbott et al 1997). In addition, anovulatory subordinate females in laboratory groups have markedly lower basal cortisol levels than ovary-intact dominants or ovariectomized females (Baker et al 1999, Johnson et al 1996, Saltzman et al 1994, 2004.…”

Social suppression of cortisol in female marmosets: Role of luteinizing hormone/chorionic gonadotropin

“…Morning basal (i.e., non-stressed) cortisol concentrations decline markedly within 6-7 weeks following the onset of social subordination and anovulation, and can remain low for months to years (Abbott et al, 1997;Johnson et al, 1996;Saltzman et al, 1994Saltzman et al, , 1998Saltzman et al, , 2004bSaltzman et al, , in press, 2006. Diminished cortisol concentrations are associated with reduced adrenal responsiveness to adrenocorticotropic hormone (ACTH): subordinate females have basal plasma ACTH concentrations that are similar to those of dominants (Johnson et al, 1996;Saltzman et al, 2004b, in press), and therefore have reliably lower cortisol-to-ACTH ratios (Saltzman et al, in press).…”