THE ABILITY OF THE DOG TO UTILIZE VITAMIN A FROM PLANT AND ANIMAL SOURCES

Abstract

Normal puppies, taken at weaning age, were fed a vit. A deficient basal diet supplemented by vit. A in the form of cod liver oil or in equivalent amts. of its precursor, carotene in oil, or carotene in the natural state as cooked carrots. Negative control animals from each litter developed symptoms of vit. A deficiency. The normal growth requirements of the young puppy were provided for, and a slight storage in the liver was permitted, by the administration of 20 U.S.P. units of vit. A per 100 gms. of body wt. At this level, cod liver oil, carotene in oil or in carrots appeared to be equally well utilized as sources of vit. A. Greater intake of vit. A, fed as cod liver oil, resulted in a proportionately higher conc. of vit. A in the liver of the dog. Although no wt. gain advantage was afforded by the higher levels of vit. A intake, there were evidences of better nutritive condition in superior lustre and heaviness of coat.