Within-sample variation of fecal glucocorticoid measurements

Millspaugh, Joshua J.; Washburn, Brian E.

doi:10.1016/s0016-6480(03)00061-3

Cited by 79 publications

(55 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For lab processing, I thawed the samples, and then mixed pellets from each sample by hand to account for within-sample variation that can bias assay interpretation (Millspaugh & Washburn 2003). I then transferred 0.5 grams of mixed feces and 5 ml 80% ethanol to a centrifuge tube (Nunc ®, 10 ml).…”

Section: Lab Processingmentioning

confidence: 99%

Assessing the effect of roads on impala (Aepyceros melampus) stress levels using faecal glucocorticoid metabolites

Lunde

2016

Afr. J. Ecol.

View full text Add to dashboard Cite

PrefaceThe background for this study is the imminent threat of global species decline, which I believe deserve immediate attention to enable us to preserve the Earth's biosphere and ensure that future generations will inherit a functioning planet. It is in direct association with the principles of the Convention on Biological Diversity (CBD) of the United Nations, which aims to conserve biological diversity, ensure sustainable use and an equal sharing of our resources.

show abstract

Section: Lab Processingmentioning

confidence: 99%

Assessing the effect of roads on impala (Aepyceros melampus) stress levels using faecal glucocorticoid metabolites

Lunde

2016

Afr. J. Ecol.

View full text Add to dashboard Cite

show abstract

“…Furthermore, faecal GC measures can be obtained easily without handling or observing the animals , Harper & Austad 2000, Mostl & Palme 2002, Millspaugh & Washburn 2003. The metabolism and excretion of steroids differ significantly between species and sexes (Touma et al 2003, Palme 2005; therefore, non-invasive methods must be physiologically validated for each species (Rehnus et al 2009).…”

Section: Introductionmentioning

confidence: 99%

The effect of ACTH upon faecal glucocorticoid excretion in the koala

Davies¹,

Gillett²,

McAlpine³

et al. 2013

Journal of Endocrinology

View full text Add to dashboard Cite

Environmental changes result in physiological responses of organisms, which can adversely affect population dynamics and reduce resistance to disease. These changes are expressed in chronic levels of stress. The measurement of glucocorticoid (GC) concentrations in faeces is a non-invasive method for monitoring stress in wildlife. The metabolism and excretion of steroids differ significantly between species and, as a consequence, non-invasive methods must be physiologically validated for each species. Koalas (Phascolarctos cinereus) are declining in numbers through much of their range. The role of chronic stress in koala populations has not been identified. Prior to the assessment of faecal GC concentrations in wild koala populations, the excretion timing and concentrations of GCs need to be determined. In this study, we assessed a method for identifying and measuring the concentrations of GC metabolites in faecal pellets of captive koalas following ACTH treatment. The results show that an elevation of plasma cortisol concentrations, using sustained release of ACTH, results in elevated concentrations of faecal cortisol/cortisol metabolites. Taking into account the excretion time lag, an increase in faecal cortisol metabolite concentrations corresponds to the release of GCs from the adrenal cortex as early as 36 h before faecal pellet collection. The calculations of steroid partitioning of plasma cortisol showed that the ACTH-stimulated values were significantly different from the control values for the concentrations of free, corticosteroid-binding globulin-bound and albumin-bound cortisol. This study validates the use of faecal cortisol analysis to assess the activity of the hypothalamo-pituitary-adrenocortical axis in freshly collected koala faecal pellets and indicates that the method should be suitable to assess the adrenocortical status of koalas in wild populations.

show abstract

“…This is of particular concern for field researchers who are limited in their storage and transport capabilities of fecal samples [Ziegler & Wittwer, 2005]. For example, most studies that have examined the effects of variables such as storage techniques [Khan et al, 2002;Lynch et al, 2003], environmental conditions to which samples are exposed [Washburn & Millspaugh, 2002], within-sample hormone variation [Millspaugh & Washburn, 2003], and dietary variation [von der Ohe et al, 2004;Wasser et al, 1993] have found significant effects.…”

Section: Introductionmentioning

confidence: 99%

Testing extraction and storage parameters for a fecal hormone method

Pappano

Roberts

Beehner

2010

American J Primatol

View full text Add to dashboard Cite

Four experiments were conducted to test different aspects of a "field-friendly" fecal hormone extraction method that utilizes methanol extraction in the field followed by storage on C18 solid-phase extraction cartridges. Fecal samples were collected from geladas (Theropithecus gelada) housed at the Bronx Zoo, and the experiments were conducted in a laboratory setting to ensure maximum control. The experiments were designed to either simulate the conditions to which fecal samples are subjected during fieldwork or improve on an existing protocol. The experiments tested the relationship between fecal hormone metabolite preservation/recovery and: (1) the amount of time a sample is stored at ambient temperature; (2) the number of freeze/thaw cycles a sample undergoes; (3) the effectiveness of different extraction solutions; and (4) the effectiveness of different cartridge washes. For each experiment, samples were assayed by radioimmunoassay for fecal glucocorticoid (GC) and testosterone (T) metabolites. Results for each of the experiments were as follows. First, storage at ambient temperature did not affect hormone levels until 4 weeks of storage, with significant increases for both GC and T metabolites at 4 weeks. Second, hormone levels significantly decreased in samples after two freeze/thaw cycles for GCs and six freeze/thaws cycles for T. Third, for both GCs and T, hormone extraction using various methanol solutions was significantly higher than using 100% ethanol. Finally, using a 20% methanol solution to wash cartridges significantly increased GC levels but had no effect on T levels. These results suggest that, when utilizing C18 cartridges for fecal steroid storage, researchers should consider several methodological options to optimize hormone preservation and recovery from fecal samples.

show abstract

Within-sample variation of fecal glucocorticoid measurements

Cited by 79 publications

References 23 publications

Assessing the effect of roads on impala (Aepyceros melampus) stress levels using faecal glucocorticoid metabolites

Assessing the effect of roads on impala (Aepyceros melampus) stress levels using faecal glucocorticoid metabolites

The effect of ACTH upon faecal glucocorticoid excretion in the koala

Testing extraction and storage parameters for a fecal hormone method

Contact Info

Product

Resources

About