The Effect of the Protein Level of the Ration Upon Certain Blood Constituents of the Hen

THE extensive use of chemical methods of blood analysis in studies of human diseases has led to their application in the study of the blood chemistry of domestic and experimental species. Studies of the effect of dietary or seasonal changes upon certain constituents of the blood of the chicken have been made by Thompson and Carr (1923), Thompson and Powers (1925), Hogan, Shrewsbury and Kempster (1929), Horvath (1930), Elvehjem and Neu (1932) and others. It was the objective of this investigation to determine whether the amount of protein in the ration affected the level of non-protein nitrogen, uric acid, urea nitrogen, creatine, and blood sugar in the blood of hens. If an effect were demonstrated, the methods employed might serve as a rapid means of studying protein feeding. EXPERIMENTAL Two groups of S. C. White Leghorn hens which had received rations differing in their protein content for more than six . . .