Validation of a fecal glucocorticoid metabolite assay for collared peccaries (Pecari tajacu)

J Zoo Wildl Med. 2012 Jun;43(2):275-82. doi: 10.1638/2011-0046.1.


The possibility of assessing endogenous adrenal activity in the collared peccary (Pecari tajacu) was tested by using an adrenocorticotropic hormone (ACTH) challenge in a fecal glucocorticoid metabolite (FGM) assay. Feces were collected from 12 captive adult male peccaries beginning 48 hr prior to challenge; six of these animals received the challenge as an ACTH injection and the other six were injected with saline solution. Feces collection ended 120 hr after injections. As a control, feces were collected for eight consecutive days from another six adult male peccaries that remained in their original mixed-sex herds in semiconfined paddocks. All feces samples were freeze-dried, extracted by an ethanol vortex method, and assayed for glucocorticoids by means of an enzyme immunoassay. FGM concentrations were compared between the treatments by a repeated measures analysis of variance (ANOVA) followed by a post hoc Tukey test. The assay is reliable but, instead of the usual proportion of 1:50 in ethanol (fecal mass:solvent), 1:10 is recommended for best extraction of FGM. Baseline FGM concentrations were similar among the ACTH, saline, and control treatments (29.7 +/- 11.2 ng/g(-1) dry feces) during the 48 hr before the challenge. The ACTH group reached an FGM excretion peak at 24 hr post-treatment, followed by a decline, while in the control and saline groups FGM levels remained relatively constant. Therefore, the fecal glucocorticoid metabolite assay reflects endogenous adrenal activity in the collared peccary and is a powerful tool for noninvasive stress monitoring in peccaries.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenocorticotropic Hormone / chemistry
  • Adrenocorticotropic Hormone / metabolism
  • Adrenocorticotropic Hormone / pharmacology*
  • Animal Welfare
  • Animals
  • Animals, Zoo
  • Artiodactyla / physiology*
  • Feces / chemistry*
  • Glucocorticoids / chemistry*
  • Glucocorticoids / metabolism*
  • Immunoassay / veterinary
  • Male
  • Reproducibility of Results


  • Glucocorticoids
  • Adrenocorticotropic Hormone