Abstract: Between May 1990 and January 1991, behavioral observations were made of two captive pumas (Felis concolor Linnaeus), and two captive snow leopards (Panthera uncia Schreber) in their outdoor exhibits at the Lincoln Park Zoological Gardens, Chicago, Illinois. Behaviors compared within and between species included: 1) time spend in the different habitat types; 2) time budgets for the different behaviors: laying, moving, sitting, standing, crouching, in the tree, drinking, urinating, defecating, within their inside dens, and “behavior not determined” when the identity or behavior of the individuals could not be determined; and 3) mobility of the animals within their exhibits. Also examined were: 4) preferences for different habitat types; 5) recommendations for future exhibit designs. Both species located themselves within their exhibits in a non-random manner. The majority of cats' time was spent in elevated locations (i.e., gunite ledges approximately 1-5.5 m above ground-level). Snow leopards exhibited this tendency to a greater extent than did the pumas. Both species also spent the majority of their time in the lying-down behavior; again snow leopards displayed this tendency significantly more than the pumas. Pumas were highly mobile and changed locations and behaviors in their exhibit significantly more than the snow leopards. No significant differences were noted between conspecifics in regard to habitat type preference, or mobility within the exhibit. Suggestions for future exhibit design include elevated locations for the cats to lay and look around within and outside their exhibits, caves for access to shade or relief from inclement weather, and ground surfaces to move about on. Features for exhibit design should take into consideration the natural habitat of the cat to occupy the exhibit.

Abstract: Melengestrol acetate (MGA) is the most widely used contraceptive in zoo felids, but the mechanism of contraception and the pathologic effects have not been investigated. For this study, the effects of MGA on folliculogenesis were assessed, and the association of MGA with ovarian lesions was evaluated. Comparisons were made among the histopathologic findings in the ovaries from 88 captive wild felids (representing 15 species) divided into three groups: 37 currently contracepted with MGA, eight previously exposed to MGA, and 43 never contracepted. Ninety-one percent of the felids evaluated had tertiary follicles, and no differences were noted between contracepted and uncontracepted cats. Some MGA-contracepted cats also had corpora lutea indicating recent ovulation. These results indicate that folliculogenesis is not suppressed by current doses of MGA and ovulation occurred in some cats. Therefore, the contraceptive actions of MGA do not occur by suppressing folliculogenesis, and MGA-contracepted felids likely have endogenous estrogens that may confound progestin effects on the uterus. Cystic rete ovarii was the most common pathologic finding, but they were not more prevalent in MGA-contracepted cats. These findings indicate that MGA is not associated with ovarian disease, including ovarian cancer, in contrast to the uterine lesions noted in MGA-treated cats.