Growth Inhibition and Leg Disorder in Chicks Following Parenteral Administration of Hemin and Non-Metalloporphyrins. ∗

Summary

In this study on 2-day old chicks the reversing effects of hemin on 2-ethyl-5-methylbenzimidazole and growth depression and leg deformity produced by hemin and certain non-metalloporphyrins were investigated. Hemin did not reverse the growth depressing action of EMB. Hemin and porphyrins, proto- and hemato-porphyrin, caused depression of growth below that of controls; also, hemin and protoporphyrin caused bowing of legs. That the basic porphyrin nucleus is the probable cause of this depression and leg bowing and not iron imbalance is demonstrated by similarity of action of protoporphyrin and hemin. Hematoporphyrin caused growth depression but did not produce leg bowing. Incidence of bowing was directly related to dose. Hematocrits determined at 16 and 21 days were not affected by treatment.