Folic Acid as a Growth-Factor for the Rat

Abstract

THE recent publication by Aschkenasy-Lelu and Aschkenasy¹ of their findings on the effects of folie acid on growth and blood composition in the young rat on a synthetic diet with or without adequate protein has prompted us to record a note on some early observations made on folic acid as a growth-factor. As soon as crystalline folic acid became available for biological research in 1946, an experiment was planned to investigate the effect of folic acid on the growth of rats receiving a synthetic diet. Weanling rats of the black-and-white Lister Institute strain were given at 28 days of age a diet consisting of: with 0.02 ml. cod liver oil daily and 1 ml. of a solution of B vitamins containing, per ml.: Folic acid was administered separately in daily doses of 0, 0.5, 1.0, 2.0, 4.0 or 8.0 µgm. A positive control group of rats was given a crude liver extract in a daily dose equivalent to 6 gm. original liver.