A versatile enzyme immunoassay for the determination of progestogens in feces and serum

The ability of zoos to monitor the reproductive status of their animals can vastly improve the effectiveness of husbandry/management practices, and no ninvasive methods such as fecal steroid analysis are the easiest to apply i n a zoo setting. Furthermore, enzyme immunoassay (EIA) is preferred to radi oinummoassay (RIA) as the method of quantifying hormones because EIAs do no t involve the use, storage, and disposal of radioactive materials. However, progesterone is excreted in the feces as predominantly unconjugated metabo lites (progestogens) and, until recently, antibodies able to cross-react wi th a variety of progestogens were used primarily in RIAs. An EIA using a br oad-spectrum progestogen antibody is described and applied to serum and/or fecal samples from female African elephants, black rhinoceros, white rhinoc eros, okapi, and hippopotami. The clear progestogen profiles generated in t hese species suggest that the described EIA would be as versatile as the RI A using the same antibody and could be a practical and economical alternati ve to RIAs for monitoring gonadal function via progestogen analysis in zoo species. (C) 2001 Wiley-Liss, Inc.