Carotene in the Nutrition of Dairy Calves

The necessity of vitamin A for proper growth and well being of dairy calves has been conceded quite generally for the past ten years.It has been shown that for this species the general symptoms of vitamin A deficiency are slow growth, general unthriftiness, scours, blindness, susceptibility to pneumonia, and oedema.Studies at the Pennsylvania Agricultural Experiment Station in which large amounts of cottonseed meal were fed to calves have shown definitely that supplements of cod liver oil or alfalfa hay of good quality will prevent the usual malnutrition or cottonseed meal injury that results from such feeding practice.If the injury had not progressed too far cures were affected by the same treatment.The vitamin A present in the cod liver oil and the carotene (the mother substance of vitamin A) in alfalfa undoubtedly played a major rSle in the prevention and cure of this malnutrition.Carotene dissolved in cottonseed oil, on the other hand, apparently had little or no effect in the prevention or cure of this nutritional ailment.Jones, Eckles and Palmer (11) showed very conclusively that vitamin A is indispensable in the growth of dairy calves.Bechdel, Eckles and Palmer (3) in the same year reported that calves developed symptoms of vitamin A deficiency when cod liver oil was not included in their experimental ration of corn gluten feed, casein, polished rice and butterfat.Converse and lVieigs (6) found that cows fed on timothy hay of low grade for a period of two or more years were unable to produce normal calves.Calves fed on the milk from these cows soon died.The investigators found that vitamin A in the form of carotene or cod liver oil can be added to the deficient milk rations of the calves and by doing so make them adequate for producing approximately normal growth.After depleting calves of their body store of vitamin A by feeding a basal diet composed of skimmilk, cottonseed meal, dried beet pulp and bone meal, Kuhlman, Gallup and Weaver (12) found that 5 ml. of a commercial carotene preparation fed in combination with a vitamin D supplement was as effective in relieving the vitamin A deficiency symptoms as 30 ml. of cod liver oil.