title: A rapid direct radioimmunoassay for the measurement of oestrone sulphate in the milk of dairy cows and its use in pregnancy diagnosis.
abstract: A radioimmunoassay for oestrone sulphate in unextracted samples of milk has been developed. The assay was validated by comparison with a method involving hydrolysis and extraction. The direct assay was used to measure oestrone sulphate in milk samples taken at weekly intervals throughout pregnancy in a commercial dairy herd. Concentrations of oestrone sulphate increased approximately 100 days after insemination and were maintained throughout the remainder of pregnancy in the range of 1.85-3.70 nmol/l.
mesh_terms: D000818:Animals; D002417:Cattle; D004966:Estrogens, Conjugated (USP) / Q000032:analysis*; D004970:Estrone / Q000031:analogs & derivatives* / Q000032:analysis; D005260:Female; D008892:Milk / Q000032:analysis*; D011247:Pregnancy; D011258:Pregnancy Tests / Q000662:veterinary*; D011270:Pregnancy, Animal; D011863:Radioimmunoassay
chemical_list: D004966:Estrogens, Conjugated (USP); D004970:Estrone; C017296:estrone sulfate