Properties of the Colostrum of the Dairy Cow. I. Tocopherol Levels in the Colostrum and in the Early Milk

Abstract

The tocopherol content was detd. in the colostrum and early milk from cows receiving a standard winter dairy ration, with and without supplements of vitamin A and of different levels of tocopherols. The method for determining tocopherols was essentially that developed by Quaife (Jour. Biol. Chem., In press). The data revealed no differences that could be attributed either to the breed or to the number of previous lactations. For cows receiving tocopherols at 0, 0.5 to 1-g., and 10-g. levels of supplementation during the latter stages of gestation, the cone, of these substances in the first colostrum were in the ratio of 1, 1.4, and 4.5, respectively. The average levels in the first colostrum from these 3 groups were, respectively, 7, 9, and 12 times higher than in the milk on the 8th day postpartum. The change in tocopherol cone, in the colostric fat followed a logarithmic trend which was similar for each of the exptl. groups. For a cow milked throughout the gestation period, tocopherol levels of the first postpartum secretions were much lower and the rate of decline was less than for cows having the normal dry-rest period. Calculations were made showing the total quantities of tocopherols secreted during the first 8 milkings of the colostric period and the quantities of tocopherols that a calf would receive during the colostric period through consuming colostrum from cows on the various levels of supplementation.