CONCENTRATIONS OF VITAMIN-C IN PLASMA AND MILK OF DAIRY-CATTLE

Colostrum or milk samples from 6 cows and blood plasma samples from th e cows and their calves were taken between 0 and 28 d after calving an d analyzed for vitamin C (ascorbic acid). At birth, the blood plasma c oncentration of ascorbic acid in calves ranged between 6.1 and 10.8 mu g/ml, and declined within 5 d to between 2.7 and 4.5 mu g/ml. Corresp ondingly, the concentration was twice as high in colostrum (16 mu g/ml ) than in milk at 2 d after calving (8 mu g/ml). The plasma ascorbic a cid concentration was initially lower in cows than in their calves, an d reached the same level approximately 28 d after carving.