Further Studies on the Effect of Sources of Vitamin D in the Diet of the Chicken on Storage of the Antirachitic Factor

APREVIOUS paper (1933) reports the results of a study to determine the effect of the quantity and source of vitamin D in the diet of the chicken on the storage of the antirachitic factor in egg yolk. The data obtained indicated that utilization of the vitamin D of cod liver oil at high levels was poor in comparison with that for viosterol of approximately the same potency. Since the oil content of the cod liver oil diet was necessarily high the question was raised as to whether the fat content per se or some specific substance in the oil itself was responsible. It seemed possible that the fat of the cod liver oil might have an influence upon the utilization of the vitamin D similar to that of mineral oil upon vitamin A metabolism. The study reported here was undertaken to answer this question. Data were also obtained for determining . . .