The Protein Requirement of the Chick as Influenced by Aureomycin

The protein requirement of the rapidly growing broiler has been investigated at this station over a period of several years. Since an antibiotic was not included in the original test rations but was used in more recent trials, it seemed desirable to investigate the possibility of dietary protein having been spared by aureomycin. The composition of the rations is given in Table 1. Cerelose rather than corn was used in this ration to attain the desired protein levels by adjusting only the level of soybean oil meal and methionine. The rations were fed ad libitum to groups of twenty crossbred male chicks (New Hampshire male × Barred Plymouth Rock female). The ration at each level of protein was fed with aureomycin (15 mg./kg. diet) and without the antibiotic. The six lots were distributed at random in an electrically-heated battery brooder. Individual chick weights and feed consumption by lots were recorded . . .