Determinations of Metabolizable Energy of Feeding Stuffs for Cattle

While the measurement of total nutritive values of individual feeding stuffs seems to be an impossible objective, from a critical point of view, the need for such measures, to serve as guides in feeding practice, requires continuing search for the most practicable compromise with scientific conceptions of the problem. In this spirit—after the determination of the digestible nutrients of-feeding stuffs, the next step toward more significant measurements of nutritive value is the determination of metabolizable energy, that is, the gross energy minus the energy of the feces, the urine (corrected for the nonmetabolizable energy of the protein stored) and the methane. What is the most practicable method of accomplishing this purpose? In an effort to guide the way toward this objective the authors present first, as bases of comparison, a series of experimental measurements of the percentage of the gross energy of a normal, dry ration of alfalfa hay, corn meal and linseed meal which is metabolizable, and three series of similar computed values of this ration,