| Popis: |
A detailed procedure for the estimation of estrone and estradiol-17β in the urine of the non-pregnant sow is described. It is based on the methods of Bauld (1956) and Brown (1955), and involves acid hydrolysis; ether extraction; purification by adsorption chromatography on alumina and saponification; separation of estrone and estradiol-17β by column partition chromatography; further purification of the estrone fraction with Girard's reagent; colorimetric measurement with the Kober reaction, and a spectrophotometric correction for interfering chromogenic material. Kober colors given by urinary estrogens are extracted with tetrachloroethane, containing p-nitrophenol, to decrease absorption due to impurities.The reliability of the method has been investigated and data concerning its accuracy, precision, sensitivity, and specificity are presented. |
