The Effect of Folic Acid on Embryonic Development of the Domestic Fowl

DURING the course of experiments designed to determine the folic acid requirement of laying and breeding hens (Cravens and Halpin, 1949; and Sunde et al., 1950b), certain embryonic deformities were observed. Further it was observed that a high proportion of the embryos from deficient hens died during the latter stages of the developmental period. We wish to describe herein these symptoms as well as to present data showing the effect on hatchability of injecting folic acid into the egg in varying quantities and at different times of incubation. Data showing the relation between the type of carbohydrate in the diet and the incidence of abnormal embryos and the time required to deplete the breeding hen of folic acid will also be presented. EXPERIMENTAL METHODS The management of the hens has been described by Cravens and Halpin (1949). Four to twelve Single Comb White Leghorn pullets were placed on each ration. . . .