Fecal Riboflavin of Rats Receiving Varying Intakes of Riboflavin

Abstract

Summary

The concentration of riboflavin in the stools of young rats maintained on a riboflavin deficient diet or at intakes of 10 μg or 40μg of this vitamin per day remained constant throughout a test period of 40 days and was essentially the same for all groups.

The total output of riboflavin was dependent upon the quantity of feces excreted. Rats receiving riboflavin but with the caloric intakes restricted to the extent of 50% excreted less total riboflavin than did their ad libitum controls.

Addendum. After this paper had been accepted for publication, Schweigert et al. ⁸ reported that cecectomized rats on complete synthetic rations and synthetic rations containing limited amounts of the individual B vitamins grew at the same rate as their controls. They concluded that growing rats on sucrose-containing diets did not depend to any extent on the cecum for the absorption or synthesis of these known or required factors.