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A reliable method for the confirmation of sex in Geocrinia frogs is currently unavailable. A captive colony of Geocrinia frogs was used to determine whether fecal steroid analysis could be used as a noninvasive method of sex diagnosis in mature frogs. Linear discriminate analysis, using measured concentrations of fecal hormones, also was applied to establish whether a reliable model could be developed to verify the sex of juvenile frogs. Fecal samples were collected over a 3-month period from all frogs in 2010, and again from 12 frogs in 2011. Samples were pooled for each individual and tested for testosterone metabolites (TMs) and estrone conjugate metabolites (EMs) using enzyme immunoassays. Mature male frogs had higher (P < 0.01) mean TM : EM ratios than those of mature females, with mature male and female ratio ranges being 100% distinct. Mature female frogs had higher (P < 0.01) mean EM concentrations than those of mature males, but EM concentrations overlapped between the sexes in 18.7% of cases. There was no statistical difference (P = 0.28) between mature males and females in mean or range of TM concentration, with overlap between the sexes in 75% of cases. Juveniles had hormone values similar to those recorded for mature male and female frogs. Generated discriminate rules were able to distinguish (100%) between mature males and females and correctly classified the sex of 75% of the juvenile frogs. It was concluded that fecal steroid analysis offers a promising, noninvasive approach to sex identification in Geocrinia frogs. [ABSTRACT FROM AUTHOR]

Abstract: Annual patterns of faecal cortisol metabolite (FCM) secretion were examined in six captive numbats (Myrmecobius fasciatus). The use of enzyme-immunoassay for the measurement of FCM in the numbat faeces was validated using an adrenocorticotropic hormone (ACTH) challenge and the resultant FCM measurements represent the first description of adrenal endocrinology in this species. Total overall, baseline and peak FCM mean concentrations varied according to individual, but not gender. For males, mean baseline and overall FCM secretion was higher in spring in summer (compared to winter and autumn) and was elevated during the breeding season. For females, mean baseline FCM secretion did not differ by season or breeding season, but mean overall FCM secretion was elevated during the breeding season. Thus, male (but not female) numbats display an annual change in FCM secretion that is strongly linked to their seasonal pattern of reproduction. Significant FCM elevations (n =178) were observed in response to 20 different stressors, with these stressors being allocated to one of six categories: ANIM, ENVIRO, HAND, HEALTH, MAN and UNK. The mean proportion of positive responses to each category varied according to category, season and breeding season, but did not vary by individual or gender. ANIM and HEALTH stressors elicited a higher response rate than all other categories and an increase in the number of ANIM, ENVIRO, and HEALTH stressors were observed during the breeding season. Although there were multiple stressors within the captive environment that the numbats reacted to, this did not translate into a welfare issue. [Copyright &y& Elsevier]