Plasma concentration of androstenedione during the bovine oestrous cycle

A radioimmunoassay with Sephadex chromatography for androstenedione is described. Concentrations of androstenedione in bovine peripheral blood during the oestrous cycle ranged from 80 to 100 pg/ml. There was considerable variation and no pattern suggestive of physiological significance emerged, unlike those of oestradiol and testosterone.