Abstract

Fecal corticoid levels are frequently monitored as an indirect indicator of “stress” in wildlife species, including cheetahs (Acinonyx jubatus). In zoos, cheetahs often serve as education ambassadors but the relative effect of these activities on adrenocortical function is unknown. In this study, our goal was to assess and compare fecal corticoid levels among the three separate cheetah populations maintained for educational, exhibitry, and propagation purposes at the Cincinnati Zoo and Botanical Garden. Our specific objectives are to 1) compare variations of basal and peak fecal corticoid levels among these cheetah populations; and 2) assess the correlation between corticoid levels and each individual’s temperament. Fecal samples were collected (3–7 samples/week) for 10 wk from 12 cheetahs within the 3 groups (education, 3.2 cats; exhibitry, 0.2 cats; propagation, 3.2 cats). Cat keepers (2–3/population) also completed a temperament survey for each subject animal to allow interpretation of fecal corticoid levels relative to specific personality traits. For analysis, fecal samples (n=428) were freeze-dried and extracted for measurement of corticoid levels using a validated corticosterone enzyme-immunoassay. Overall, basal corticoid levels were lower (p<0.01) in cheetahs in the education program (mean±SEM; 176±6 ng/g feces) and on public exhibit (409±71 ng/g) than for cheetahs in the propagation program (885±103 ng/g). Peak corticoid levels also were higher (p<0.01) in breeding cheetahs (2092±134 ng/g) compared to education cheetahs (484±41 ng/g) and cheetahs on exhibit (707±216 ng/g). Across populations, individuals that were tense, fearful of people or showed aggression to humans had higher (p<0.05) peak corticoid levels, whereas cheetahs that vocalized frequently or were friendly to people showed lower (p<0.01) peak values. These findings indicate that fecal corticoid concentrations may show substantial variation among cheetahs, depending on their temperament, daily stimuli and life histories. Notably, adrenocortical activity in cheetahs that serve as education ambassadors was similar to that of cheetahs maintained on public exhibit, and reduced relative to cheetahs managed for propagation at an off-exhibit breeding facility.

Acknowledgments

The authors thank Catherine Hilker and the Angel Fund for financial support of this study, and the cheetah keepers in the Cincinnati Zoo’s Cat Ambassador Program (Linda Castaneda, Alicia Sampson, Kathy Watkins), Night Hunters exhibit (Pat Callahan, Michael Land) and Mast Farm Breeding Facility (Thomas Tenhundfeld, Renee Carpenter) for completion of temperament surveys and fecal sample collection.