Effect of Protein Source on the Performance of Early Weaned Pigs

Seventy-two Yorkshire boar pigs were used to study growth rate and feed efficiency in pigs weaned at 3 weeks of age and fed either casein or soy-protein as a source of supplemental protein in corn based diets. Treatments consisted of a corn-casein diet, a corn-isolated soy protein diet, a corn-ethanol extracted soy protein diet and a corn soybean meal diet. Feed intake was not affected by source of dietary protein. Average daily gain (P<.l) and feed efficiency (P<.01) were improved when casein was the source of supplemental protein. Differences in feed efficiency were not apparent after the second week post weaning resulting in a week by treatment interaction (P<.05). Ethanol extraction of soy protein resulted in no improvement in pig performance over soybean meal as a source of supplemental protein.