The Effect of Aureomycin on the Apparent Utilization of Vitamin A by the Ovariectomized Rat

Abstract

The effect of aureomycin on the vaginal smear assay for vitamin A has been studied. Aureomycin was added to the diet at the rate of 66 mg per kilogram and the response to doses of vitamin A acetate was compared with the response obtained in the absence of the antibiotic. Standard bioassay procedures were used. Aureomycin increased significantly the response to vitamin A. This effect was relatively transient. Experiments in which aureomycin supplementation was begun 24 hours after the last vitamin A dose suggested that the effect was not a result of increased absorption of the dose. The addition of vitamin B₁₂ to the diet did not mask the effect of aureomycin on the vitamin A assay. Likewise, the addition of tocopherol to the vitamin A doses had no influence on the vitamin A assay in either the presence or absence of aureomycin. Aureomycin increased the mean response to vitamin A by 25%.