Similarity in Ejaculate-Endocrine Characteristics in Captive Versus Free-Ranging Cheetahs of Two Subspecies’

Ejaculate-endocrine characteristics were measured in 23 captive cheetahs (Acinonyx jubatus jubatus) in North American zoos and in 8 free-ranging cheetahs (A. j. raineyi) in eastern Africa (Tanzania). A standardized electroejaculation protocol was used, and numbers of motile spermatozoa were similar (p>O.05) between groups. Of the spermatozoa collected by electroejaculation, 70.6 ± 3.3 % and 75.9 ± 4.4 % were morphologically abnormal in the captive “North American ” and in the free-ranging, eastern African populations, respectively. Adrenal activity, as measured by an acute, temporal rise and fall in serum cortisol levels during and after electro-ejaculation, was no different (p> 0.05) between groups. Although serum luteinizing hormone (LH) levels were less (p< 0.05) In the free-ranging than in the captive animals, serum testosterone concentrations were similar. The data indicate that the comparatively poor reproductive performance of cheetahs maintained in zoological parks is not attributable to a captivity-induced response afflicting the male. Furthermore, there is no evidence that ejaculate/endocrine characteristics differ between the two subspecies. Because adrenal /gonadal activity and the number of pleiomorphic spermatozoa are similar between the test groups, the results suggest that spermatozoa