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A simplified method for extracting androgens from avian egg yolks
Corinne P Kozlowski1, Joan E Bauman, D Caldwell Hahn
1Research Department, Saint Louis Zoo, St. Louis, MO 63110, USA. kozlowski@stlzoo.org
Abstract:
Female birds deposit significant amounts of steroid hormones into the yolks of their eggs. Studies have demonstrated that these hormones, particularly androgens, affect nestling growth and development. In order to measure androgen concentrations in avian egg yolks, most authors follow the extraction methods outlined by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). We describe a simplified method for extracting androgens from avian egg yolks. Our method, which has been validated through recovery and linearity experiments, consists of a single ethanol precipitation that produces substantially higher recoveries than those reported by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). Zoo Biol 28:137-143, 2009.

