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We validated a radioimmunoassay-based method quantifying fecal glucocorticoid metabolites (FGMs) from captive male and female Richardson’s ground squirrels Urocitellus richardsonii. Blood samples were drawn to explore the correlation between plasma cortisol and FGM concentrations. We also injected groups of squirrels with normal saline (CTL; control), adre-nocorticotropic hormone (ACTH; stimulating adrenal activity), or dexamethasone (DEX; suppressing adrenal activity). Potential correlations between stress and behaviour were explored through quantification of fecal pellet production and the intervention necessary to elicit defecation, as well as the behaviour of subjects in the context of handling. Changes in plasma cortisol concentration between capture (baseline), and following handling (stress-induced) were also quantified for free-living squirrels. While glucocorticoid concentrations recovered from feces during our captive-animal study were not well correlated with plasma cortisol concentrations, and uncorrelated with defecation or behaviour, FGM concentrations did reflect the activation of the hypothalamic-pituitary-adrenal (HPA) axis. FGM concentrations increased significantly during initial captivity, but declined to baseline level as individuals acclimated to the novel environment. Injection of subjects with ACTH increased FGMs above baseline, confirming activation of the HPA axis. Plasma cortisol concentrations increased significantly with induced stress, indicating that capture and handling activated the glucocorticoid stress response even among previously handled, free-living subjects. Our findings validate a non-invasive tool that will afford new insight into the physiological processes underlying social, reproductive and antipredator behaviour of Richardson’s ground squirrels.

The endangered Puerto Rican crested toad (Peltophryne [Bufo] lemur) has been held and bred in zoos for release into protected areas in Puerto Rico since 1982. In 2004, several cases of a novel syndrome of skin changes in toads were noticed at the Toronto Zoo. A total of 21 toads were found to have similar lesions and the condition has been seen in several other groups of toads in subsequent years. Affected toads show an uncharacteristic sheen of dark-brown leathery skin, followed by recurring dysecdysis, reduced appetite, weight loss, and death from secondary causes. Histologically the condition is characterized by epithelial hyperplasia and hyperkeratosis, ulceration, and the presence of superficial mats of bacterial and fungal agents. No etiology has been identified and to date toads have not permanently responded to treatment with various pharmaceutical and nutritional therapies.

The captive breeding program for the endangered Puerto Rican crested toad (Peltophryne [Bufo] lemur) has been hampered by an undiagnosed condition called “Brown Skin Disease” (BSD). Toads develop widespread skin darkening, skin thickening and abnormal shedding and eventually succumb to a chronic loss of viability. This project evaluated the marine toad (Bufo marinus) as a model for the PRCT, examining vitamin A deficiency as a potential cause of BSD. Wild caught marine toads had significantly higher liver vitamin A concentrations (61.89 ± 63.49 µg/g) than captive born marine toads (0.58 ± 0.59 µg/g); P

This study investigates the use of an enzyme immunoassay to measure keratin glucocorticoid concentrations in reptilian shed skins. Keratin glucocorticoid concentrations were compared to fecal glucocorticoid concentrations during the period of keratin growth in the African House Snake (Lamprophis fuliginosus) and the Eastern Massasauga Rattlesnake (Sistrurus catenatus catenatus). Biochemical validation was performed for the shed skin and fecal corticosterone enzyme immunoassays in the African House Snake. Biological and physiological validations were attempted in the African House Snake. A statistically significant positive association was detected between shed skin corticosterone and the mean fecal corticosterone metabolites from 3 weeks before to 1 week after the previous ecdysis in the African House Snake. A statistically significant difference was not detected between the shed skin corticosterone concentrations of the minimally handled control and the weekly handled (or experimentally stressed) African House Snakes. Adrenocorticotropic hormone stimulation did not result in the physiological validation anticipated for shed skin corticosterone concentrations in the African House Snake.

AVIAN bornavirus (ABV), a newly discovered agent, has been identified as the causal agent of proventricular dilation disease (PDD) in psittacine birds (Honkavuori and others 2008, Kistler and others 2008). Subsequent research, including bird inoculation studies (Gancz and others 2009, Gray and others 2010) and outbreak investigations (Kistler and others 2010) have provided strong supporting evidence. PDD is a significant pathological syndrome, with high mortality affecting primarily psittacine birds, that has been reported worldwide since the late 1970s. Characteristic pathological findings of PDD …