Protein Levels for Pigs as Studied by Growth and Self-Selection

Abstract
The effect of protein level on growth has been compared with the protein levels selected by pigs offered the same diets as corn and protein supplement free choice. Comparison of the conditions of this study with the conditions of the studies of others emphasize the variations that may be applied to controlled experiments studying essentially the same question, and lead to the conclusion that minimum protein allowances for growing swine are not fixed quantities and may be stated precisely only by listing the specific conditions to which the precise allowances apply. Under the conditions of these tests, in drylot, the minimum protein allowance appears to be 14 to 16 percent from weaning to 100 lb. When the same protein level is fed for the entire growth period from weaning to 200 lb., the minimum allowance appears to be 12 to 14 percent. On alfalfa pasture, according to the growth test the minimum protein allowance appears to be 12 to 14 percent from weaning to 200 lb., although the higher protein level appears advisable for pigs under 100 lb. Pigs on pasture that had corn and supplement available, free choice, selected protein levels at 10.8 percent from weaning to 100 lb. and 10.0 percent from 100 to 200 lb. Copyright © . .