The effects of dietary gentian violet upon certain physiological parameters of broiler chickens were studied. Gentian violet exhibited no effect upon growth rates or feed conversion ratios at dietary levels of 16, 32, or 64 micrograms/g. In vitro intestinal absorption of methionine and glucose was also unaltered. Dietary gentian violet significantly increased hemoglobin concentration without an effect on packed cell volume. Furthermore, commercial gentian violet containing preparations, when incorporated into the diet, resulted in increased intestinal absorption of Fe59 but this increase was dependent upon type of inert carrier used. Dietary gentian violet alleviated some of the growth suppression caused by dietary aflatoxin; however, no effect was observed on plasma pigmentation. These data suggest that dietary gentian violet possesses effects other than those for which it has been traditionally employed.