The Nutrition of the Young Ayrshire Calf

MacDonald, 1953) it was observed that when each calf of a group was given the same quantity of a standard diet that produces muscular dystrophy, a very large variation occurred in the time of onset of clinical signs of the disease.With some diets, one calf was observed to show no signs, yet all its contemporaries, managed and fed under identical conditions, died.The groups of calves for these experiments were bought in the market, and in most instances little was known regarding either their nutritional history during the first few days of life, or the nutritional status of their dams.The initial reserves of the calf in respect of a-tocopherol were thought to be at least one factor responsible for the above variation.The marked seasonal variation in the incidence and severity of both the experimentally produced disease (Blaxter, Wood & MacDonald, 1953) and of that which occurs naturally (Slagsvold & Lund- Larsen, 1934; Hjarre & Lilleengen, 1936) with maximums in the late winter and early spring also suggests that variation in the tocopherol reserves of the calves is important.It is known that the tocopherols are present in large amounts in the colostrum of rats (Mason & Bryan, 1940), women (Abderhalden, 1945b), and cows (Parrish, Wise & Hughes, 1947).In cows the concentration was found to be ten to twelve times that of the milk in full lactation.When calves suckle, the colostral tocopherols rapidly appear in the blood serum (Parrish, Wise, Latschar & Hughes, 1950) and the serum tocopherols of the calf increase nine-to tenfold.On this evidence, Parrish (1949) concluded that colostral transfer was far more important than placental transfer in supplying the calf with tocopherols.With rats, Mason & Bryan (1938, 1940) showed that placental transfer of vitamin E was negligible as gauged by the time of onset of testicular degeneration in the offspring.Tocopherols are, however, present in the blood and liver of newborn infants (Abderhalden, 1945a, b), lambs, kids, piglets (Whiting & Loosli, 1948) and calves (Parrish et al. 1950) that have never suckled their mothers, or received any food.Many studies with cows (Scherer, 1946;