The many uses of non‐invasive faecal steroid monitoring in zoo and wildlife species

Abstract

During the past two decades, techniques for faecal steroid analysis have been developed and have been used for research with mammalian, bird and, to a lesser extent, reptile, amphibian and fish species. Various techniques for the analysis of reproductive (oestrogen, androgen, progestagen) and adrenocortical (glucocorticoids) steroid hormones have been established and have been applied to a wide range of research questions studying captive and free‐ranging wildlife, as well as domestic and laboratory species. Because of species‐specific differences in steroid metabolism in even closely related species, careful validation of assay methods is necessary in order to generate meaningful and accurate results. For future research and management of free‐ranging and captive wildlife, the great potential of non‐invasive endocrine monitoring will be utilized more than ever. In light of this, captive wildlife species are ideal research subjects, as longitudinal sample collection is possible and studies connecting physiology, endocrinology, reproduction and stress with various social and/or environmental factors can be carried out and can be analysed to determine how they impact animal health.

Assessment of reproductive function in southern African spiny mice (Acomys spinosissimus) using faeces as hormone matrix

“…Faecal samples have been used in various rodent species to monitor male and female reproductive activity (Billitti et al 1998;Schwarzenberger 2007;Busso & Ruiz 2011), and our study adds to the list by demonstrating that reproductive function can be monitored in male and female spiny mice by measuring respective faecal hormone metabolites. The established techniques could become invaluable as continuous sampling is now possible on an individual level making long term studies more feasible, simultaneously improving the ethical basis for respective experiments as animals would not necessarily have to be euthanased for sample collection.…”

“…The sex steroids, androgens and progestagens, are primarily secreted by the testes and corpus luteum, respectively, and metabolized in the liver before being excreted via urine or faeces; in the latter case typically in an unconjugated form (Touma & Palme 2005;Schwarzenberger 2007). Due to the species-specific differences in hormone metabolite excretion (Palme et al 1996;Busso et al 2005) and the presence of different steroid metabolites in the excreta of even closely related species (e.g.…”

“…As frequent collection of blood for hormone analysis has proven challenging especially in free-ranging non-domesticated animals, as well as comparatively small species like many rodents including Acomys, alternative sampling methods have often been developed for species where repeated blood collection is not feasible (Cavigelli et al 2005;Valades et al 2012). One well-established approach to monitor reproductive endocrine function in small, non-domesticated animals is through the use of faeces as a hormone matrix, as faeces can be non-invasively collected and therefore animals are usually not disturbed during sample collection (Schwarzenberger 2007;Frynta et al 2009). Faeces have therefore been used in order to characterize reproductive activity in terms of determining oestrous cycle length, pinpointing ovulation, or monitoring pregnancy as well as seasonal patterns of reproduction in a variety of rodents (Kuznetsov et al 2004;Busso et al 2005;Cavigelli et al 2005;Busso et al 2007).…”

Comparison of two methods for glucocorticoid evaluation in maned wolves

“…Finally, noninvasive methods allow information to be obtained retrospectively, as faecal samples represent average hormone production a certain time ago . Researchers and conservationists in various animal species (for a review, see , Schwarzenberger 2007) have extensively used these techniques, which are now widely accepted as effective for monitoring glucocorticoid levels. However, using these techniques to reliably assess an animal's adrenocortical activity is not that simple and straightforward to apply.…”

<b>Monitoramento das oscilações anuais nos níveis de testosterona plasmática e andrógenos fecais de machos de jararaca-ilhoa (<i>Bothrops insularis</i>) mantidos em cativeiro</b>

“…As vantagens da sua utilização são a facilidade de obtenção, simples manuseio e conservação, redução dos riscos causados pela contenção tanto para o animal quanto para o operador, maior confiabilidade dos resultados devido à ausência de estresse, além da possibilidade de colheita seriada de amostras e avaliação em animais de pequeno porte (SCHWARZENBERGER et al, 1996;VAZ GUIMARÃES, 2003;KERSEY;DEHNHARD, 2014). No entanto, essa técnica também apresenta desvantagens, tais como: a degradação microbiana dos metabólitos hormonais após a defecação, o grande número de metabólitos gerados a partir de um único hormônio e a necessidade de sua validação para cada espécie e grupo hormonal a ser avaliado (BUCHANAN;GOLDSMITH, 2004;PALME, 2005;SCHWARZENBERGER, 2007).…”