Effects of Dietary Arsanilic Acid on Chicks

THE growth response in chicks re-sulting from dietary supplementa-tion with arsenicals has been found to be about equal to that obtained with anti-biotics. Frost (1953) has reviewed the discovery and elucidation of this phenom-enon. Published information concerning the toxicity of arsanilic acid for the chick is limited. Frost (1953) reported data show-ing that the deposition of arsenic in chicken tissue resulting from dietary arsanilic acid is a function of the level in the feed. Arsenic was found to be non-cumulative in tissue when a compara-tively low level of arsanilic acid was fed. Elam et al. (1953) reported that ar-sanilic acid increased growth of chickens and decreased the number of Clostridia in the feces as did several antibiotics. This finding suggests that the mechanism of growth stimulation might be the same for antibiotics and arsenicals. Waibel et al. (1952) reported that dietary thiamine was spared by penicillin in a purified ration for chicks. Waibel et al. (1954) described the inexplicable disappearance of the growth stimulating effect of penicillin in one par-ticular environment. In the present experiments the effects of arsanilic acid and penicillin were com-pared in the above mentioned environ-ment with complete and thiamine defi-cient diets in a search for further evidence Published with the approval of the Director o