CHARACTERIZATION OF ESTROGENS IN THE BOVINE12

Abstract
Estrone, estradiol-17[beta] and estradiol-17[alpha] were identified in bovine placental extracts by chromatography on paper, formation of acetates, Kober reaction, bioassay and absorption spectra in sulfuric acid. A FeCl3-Fe(CN)6 reacting compound with a migration rate on paper chromatograms similar to estradiol-17[beta] was detected in extracts of ovaries from non-pregnant cows but in quantities too low for further identification. Maternal adrenals and ovaries and fetal adrenals and testes from two cows pregnant 256 and 265 days did not yield detectable quantities of estrogens. The placenta appears to be the principal source of estrogens in the pregnant bovine.