Cortisol and corticosterone are steroids produced by the adrenal cortex in response to
stress. Excreted corticosteroids, reflecting a number of hours of steroid secretion,
provide a more integrative measure of stress response than a serum sample collected at a
single moment in time. Cortisol is the major corticosteroid secreted in primates whereas
corticosterone is the major corticosteroid in bird and rodent serum. Both cortisol and
corticosterone have been measured in mammalian fecal extracts.
Major Applications
Comparison of basal stress levels across individuals
Estimation of the stressfulness of events
Evaluation of individual reactivity
Assessing animal well-being and conservation status
Capabilities
Fecal Steroid Extraction
Steroids are extracted from fecal samples using a solid phase method that provides a
purified extract that minimizes contaminant interference with immunoassay.
Fecal Cortisol
Fecal cortisol is assayed using a highly specific [I125]Cortisol
radioimmunoassay. We have validated this assay for use with fecal extracts with baboons,
rhesus macaques, chimpanzees, sooty mangabeys, longtailed macaques, and sifaka.
Fecal Corticosterone
Fecal cortisol is assayed using a highly specific [I125]Corticosterone
radioimmunoassay. We have validated this assay for use with rodent fecal extracts.
