The Comparative Antirachitic Efficiency of Irradiated Ergosterol, Irradiated Yeast, and Cod Liver Oil for the Chicken

Abstract

Irradiated yeast and irradiated ergosterol dissolved in linseed oil, corn oil, or cod liver oil are less effective than the rat equivalent amount of cod liver oil for calcification in the chicken. It required from 15 to 20 times as many rat units of vitamin D per unit of feed in the form of irradiated ergosterol as in the form of cod liver oil for normal bone formation. Cod liver oil did not increase the antirachitic efficiency of irradiated ergosterol for the chicken. Irradiated ergosterol proved somewhat more efficient than irradiated yeast when equivalent rat units of vitamin D were fed. Under the conditions of the experiments, the chick required a minimum of approximately 7 rat units of vitamin D per 100 gm. of ration from cod liver oil for normal calcification.