Effect of the Prepartal Diet of the Cow on the Placental and Mammary Transfer of Tocopherols to the Calf

Abstract

A study was made of serum tocopherol levels in calves, at birth and during the first month of life. The calves were from cows fed either typical unsupplemented barn rations or similar rations supplemented during the terminal stages of gestation with vitamin A or tocopherols, or both. The levels of supplemental tocopherol fed the dams were 0.5–1, 4, 5 and 10 gm daily. The first food the calves received was colostrum from their respective dams, followed later by a whole milk and grain-roughage diet. Supplements fed the dams prepartally did not markedly affect the serum tocopherol levels in their newborn calves. Tocopherols per 100 ml of serum were 44 ± 31 µg in calves from unsupplemented cows and only 79 ± 20 µg in those from cows supplemented at the highest level. Calves born with low serum tocopherol levels seemed to be as vigorous and healthy at birth as did those having the highest levels. The serum tocopherol levels of newborn calves increased three- to 9-fold following the ingestion of colostrum. The highest levels were found in calves whose dams received large amounts of supplemental tocopherols, but considerable individual variation in response was noted. By the 28th day after birth, tocopherol concentrations in calves were lower than during the period of colostrum feeding, and values for calves from supplemented cows were within the same range as those for calves from the unsupplemented. Decreases in serum tocopherol levels were observed in calves that were diarrhetic.