The Quality of Protein of Normal and High Protein Corn for Growing Swine

Abstract

The quality of the protein of several samples of normal and high protein corn for growing swine was compared using nitrogen balance techniques. The value of the protein of samples of corn containing 10.1 and 11.4 percent of protein was found to be approximately the same. When samples of corn containing 10.6 and 14.9 percent of protein were compared, the percentage of the apparently digested nitrogen retained from the 10.6 percent protein corn was significantly greater than for the high protein (14.9 percent) corn. The addition of calculated excesses of lysine and tryptophane to both diets largely eliminated the previously demonstrated differences in percent of apparently digested nitrogen retained. Data obtained from studying two samples of high protein corn (13.9 and 12.4 percent of protein) compared separately with those obtained with a sample of normal corn (9.1 percent of protein), each being supplemented with two different protein supplements to give diets containing approximately 17 percent of protein, indicated that: (1) greater nitrogen retention and daily gains were obtained when normal protein corn was fed than when high protein corn was used in the diet, and (2) the difference between the two protein supplements used was not significant. Copyright © . .