Measuring Glucocorticoid Metabolite Levels, Behavioral Profiles, and Weight Gain in Two Hand-reared, Captive Clouded Leopards (Neofelis nebulosa): A Preliminary Assessment

Abstract

Clouded leopards (Neofelis nebulosa), arguably the most distinct Pantherinae, or “big cat,” species, are currently threatened by population decline in situ and ex situ. What little is known about this cat’s behavior comes from captive studies. Modern research is focused on defining optimal rearing and mate-pairing protocols to mitigate severe mate incompatibility in this species. Evaluating the welfare of captive clouded leopards commonly entails the non-invasive measurements of behavioral ratings from the animals’ keepers and glucocorticoid (“stress” hormone) metabolite concentrations in feces (fGMs). I assessed the welfare of two juvenile females born and hand-reared at Nashville Zoo at Grassmere (NZAG) by examining corticosterone (type of glucocorticoid) metabolite concentrations, weight gain, and behavioral ratings. A three-month period of fecal collections revealed baseline concentrations of 273.5 [+ 0.4 SD] and 293.5 [+ 0.3 SD] nanograms of corticosterone metabolites per gram of fecal mass for these cubs, Sip Saam and Natida, respectively. Behavioral ratings did not differ notably; each received a mean score of approximately 4.5 out of 5. Growth rate (weight gain/day) was similar between individuals (y = 0.0452x, y = 0.0462x, r2 = 0.99). Baseline fGM levels were higher than most data reported for adult clouded leopards. This study reports the first investigation of a relationship between weight gain and fGM concentration in juvenile clouded leopards, of which I found no correlation. My data will be presented to the Association of Zoos and Aquariums’ Clouded Leopard Species Survival Plan® to assist with future pairing recommendations. These data can also be used in future studies with these two individuals to investigate the consistency of fGM levels throughout their lifespan.