Effect of Antibiotics on the Protein Requirement of Broilers

Abstract

MOORE et al. (1946) found that streptomycin caused growth stimulation in chicks while Stokstad and Jukes (1950) and Whitehill et al. (1950) showed that chick growth was stimulated by aureomycin. Scott and Glista (1950), using a corn-soybean oil meal ration fortified with known vitamins, found that aureomycin did not stimulate growth except for a slight response during the first few weeks with ab libitum feeding and not at all when feed intake was equated. Matterson et al. (1951) found that of the antibiotics—streptomycin, aureomycin, penicillin, terramycin and bacitracin—the first named was the least effective in promoting growth response in chicks. These latter workers point out that their data as a whole suggest that the better the quality of the ration with respect to protein and vitamins, the less the growth response obtained by supplementing the ration with antibiotics. It may be significant that the diet used by Scott . . .