Fecal steroid evaluation to monitor reproductive status in wild ungulate females using enzyme immunoassay commercial kits

Abstract

Analysis of reproductive hormones in fecal samples is necessary for the noninvasive monitoring of reproductive status in free-ranging species. The aim of the present study was to establish an easy noninvasive method to monitor reproductive status in wild ungulate females. Feces were collected daily, weekly, or three or four times a week directly from the soil for a period ranging from 1 to 9.8 mo. Fecal estradiol and progestagens were monitored in nine wild ungulate females (Barbary sheep, Ammotragus lervia [n = 3]; European bison, Bison bonasus [n = 1]; auroch, Bos taurus primigenius [n = 2]; sitatunga, Tragelaphus spekii gratus [n = 2]; and Indian rhinoceros, Rhinoceros unicornis [n = 1]) by using commercially available enzyme immunoassay kits prepared for human serum or plasma. In the species evaluated in this study, luteal phase, abortion, and gestation patterns corresponded closely with changes in fecal progestagens. Luteal phase and gestation values differed significantly (P < 0.001) from basal values, whereas progestagens values after abortion were not significantly different (P > 0.05) from basal values. For estradiol excretory patterns, follicular phase and pregnancy values differed significantly (P < 0.001) from basal values, but differences between values after abortion and basal values were not significant (P > 0.05); length of estrous cycles were clearly defined through estradiol data. This study demonstrates that ovarian function in the wild ungulate females studied can be monitored by enzyme-linked immunosorbent assay (ELISA). Therefore, ELISA methodologies used here could be a practical alternative to other ELISAs that require more complex procedures or whose commercial availability is difficult. Copyright 2011 by American Association of Zoo Veterinarians.