Demonstration of a β-casomorphin immunoreactive material in the plasma of newborn calves after milk intake

摘要: Abstract Blood was collected from newborn calves before and after their first milk intake birth; extracts of plasma were assayed by radioimmunoassay for the presence β-casomorphin-7 immunoreactive materials. No β-casomorphin immunoreactivity found in samples ingestion; however, ingestion a material detected. Chromatographic characterization showed that this not identical with but might rather represent precursor thereof. The proved resistant to enzymatic attack during 30-min incubation period at 37°C calves, whereas degraded under these conditions. A physiological significance eventually cleaved such any site mammal is suggested.