Further studies of organic factors required for prevention of anemia in chicks.

The results of studies in several laboratories (l-3) have shown that folic acid is required for the prevention of anemia in the chick. The antianemic effect of P-pyracin lactone when administered together with the fermentation Lactobacillus casei factor (LCF), the folic acid conjugate of Hutchings, Stokstad, Bohonos, and Slobodkin (4), has been demonstrated by Scott, Norris, Heuser, and Bruce (5). In earlier studies reported by Scott, Norris, Heuser, Bruce, Coover, Bellamy, and Gunsalus (6) cr-pyracin lactone was found to prevent anemia in chicks fed a diet containing factor S concentrate from yeast, described by Schumacher, Heuser, and Norris (7). Later it was found that the supply of factor S concentrate used in this study contained a larger amount of folic acid than usual, chiefly in the conjugate form. Studies with factor S concentrate conducted in this laboratory by Hill (8) and by Scott and associates (5, 6) have consistently shown a slight but positive effect upon hemoglobin formation by this preparation, which at times could not be accounted for in terms of either folic acid or pyracin content of the preparation. Since pyracin had been found to be active in the prevention of anemia in chicks when supplied together with folic acid conjugate, and since factor S appeared to have some effect upon hemoglobin formation in the chick, an investigation was undertaken to determine (a) whether pyracin is required for the prevention of anemia in the presence of free folic acid, and (b) whether factor S contains an antianemic factor not identical with folic acid or pyracin. The results of the investigation are presented in this report.