Cellulose in Purified Diets for Chicks

DAVIS and Briggs (1947) reported that the addition of cellulose to a typical purified diet for chicks produces a significant increase in the growth of these animals. Hoelzel and Carlson (1947) suggested that the addition of cellulose, which they consider an inert material, has the effect of increasing the proportions of fat, protein, and other constituents in the diet and that the growth response obtained may be explained on this basis. This interpretation has been questioned by Davis and Briggs (1948) and Guerrant (1948). It has been observed here that the addition of 4 percent casein to a purified diet containing 18 percent casein, 10 percent gelatin, and 0.3 percent cystine produces a growth response in chicks. Previous work by Briggs, Luckey, Elvehjem and Hart (1943) and Lepp, Moore, Elvehjem and Hart (1947) has demonstrated that supplementation of a purified diet with vitamin C and additional pteroylglutamic acid may also . . .