Natural Versus Chorionic Gonadotropin-lnduced Ovarian Responses in the Clouded Leopard (Neofelis nebulosa) Assessed by Fecal Steroid Analysis'

The clouded leopard (Neofelis nebulosa) is an endangered species difficult to propagate in captivity because of sexual incompatibility between paired individuals. Fecal estradiol (E2) and progesterone (P4) metabolites were quantified in 14 females to noninvasively monitor seasonal reproductive patterns and compare ovarian responses to natural mating vs. exogenous gonadotropins. Increased E excretion was associated with behavioral estrus or eCG treatment, whereas elevated P,4 metabolites were observed during natural and hCG-induced pregnant and nonpregnant luteal phases. On the basis of fecal E, profiles, duration of the estrous cycle was 24 2 days, with estrus lasting 6 1 days. Mean gestation length was 89 2 days, whereas duration of the nonpregnant luteal phase was 47 2 days. Females experienced a seasonal anestrus during the late summer and early fall. One female demonstrated a lactational anestrus after the birth of three cubs. On nine occasions, clouded leopards ovulated spontaneously (based on elevated fecal P4 metabolite concentrations) in the absence of mating. Patterns of eCG-stimulated E2 excretion were similar to those associated with natural estrus and were unaffected by eCG dosage (25, 50, or 100 IU). In contrast, post-hCG P4 metabolite profiles varied considerably, with responses including anovulation, attenuated luteal P4 metabolite production, and hyperstimulated luteal function. In some females, compromised luteal function after ovu-lation induction appeared to be due to the presence of mature CL from previous spontaneous (without copulation) ovulations at the time of gonadotropin treatment. Duration of post-hCG P,4 metabolite excretion was reduced-40 % in these individuals compared to females with no evidence of active luteal activity. In sum, these are the first data describing the ovarian cycle of this endangered species. Th