title: Validation of an enzyme immunoassay for the measurement of faecal glucocorticoid metabolites in Eurasian (Lynx lynx) and Iberian lynx (Lynx pardinus).
abstract: Stress hormone levels are important indicator of an animal's well-being, as stress has harmful effects on reproduction, growth and immune function. The development of enzyme immunoassays (EIA) to monitor faecal glucocorticoid metabolites (fGM) contributes a powerful tool to assess an animal's adrenal status non-invasively. We aimed to identify a suitable EIA for monitoring fGM by assessing the suitability of six different EIAs for detecting quantitative changes in fGM concentrations in response to an ACTH challenge test in Eurasian lynx. FGM were characterised in a male Eurasian lynx that received an injection of (3)H-cortisol. Using HPLC analyses radiolabeled metabolites were compared with immunoreactive metabolites. The second aim was to biologically validate the established EIA for monitoring adrenocortical activity of captive Iberian lynxes after a translocation to new enclosures in relation to behaviour. Additionally faecal samples of ten pregnant Iberian lynxes from the peripartal period were analysed. The ACTH challenge revealed an 11β-hydroxyetiocholanolone EIA as the most sensitive assay to reflect acute fGM elevations in the Eurasian lynx. HPLC immunograms demonstrated that the 11β-hydroxyetiocholanolone EIA measured significant amounts of immunoreactivities corresponding to radiolabeled metabolites with strong similarities across both lynx species. Additionally, HPLC and GC-MS analyses confirmed the presence of 11β-hydroxyetiocholanolone in faeces of both, the Eurasian and the Iberian lynx. Longitudinal fGM profiles of Iberian lynx revealed increases in concentrations associated with management events. During the peripartal period, however, fGM concentrations were not significantly elevated. Our results show that the 11β-hydroxyetiocholanolone EIA is a reliable tool to assess fGM in both lynx species.
authors: Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 13, D-10315 Berlin, Germany. Electronic address: pribbenow@izw-berlin.de.
authors: Susanne
authors: S
authors: Pribbenow
authors: Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 13, D-10315 Berlin, Germany. Electronic address: jewgenow@izw-berlin.de.
authors: Katarina
authors: K
authors: Jewgenow
authors: Center for Captive Breeding of the Iberian Lynx "El Acebuche", Huelva, Spain. Electronic address: astridvgu@me.com.
authors: Astrid
authors: A
authors: Vargas
authors: National Center for Captive Breeding of the Iberian Lynx, 8375-082 Messines, Portugal. Electronic address: rodserra@gmail.com.
authors: Rodrigo
authors: R
authors: Serra
authors: A.N. Severtsov Institute of Ecology and Evolution RAS, 33 Leninski Prospect, Moscow 119071, Russia. Electronic address: snaidenko@mail.ru.
authors: Sergey
authors: S
authors: Naidenko
authors: Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 13, D-10315 Berlin, Germany. Electronic address: dehnhard@izw-berlin.de.
authors: Martin
authors: M
authors: Dehnhard
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004777:Environment; D005243:Feces / Q000737:chemistry*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D005938:Glucocorticoids / Q000032:analysis* / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007124:Immunoenzyme Techniques / Q000379:methods*; D046008:Lynx / Q000502:physiology*; D008297:Male; D011247:Pregnancy; D012098:Reproduction / Q000502:physiology
chemical_list: D005938:Glucocorticoids; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone
keywords: ACTH; GC–MS; HPLC immunogram; Lynx; Non-invasive; Stress