Influence of Protein Intake, Energy Intake and Stage of Gestation on Protein Status of the Gestating Gilt

dietary lysine had 35, 40 and 65 percent greater rate of gain, gain: feed ratio and gain: protein ratio, respectively, than those pigs fed the corn-soybean meal diet at 0.9 percent lysine and 17.9 percent crude protein. At 1.0 percent lysine (14.3 percent protein), the corn-whey-yeast diet produced 25, 35 and 59 percent greater average daily gain, feed efficiency and protein efficiency ratio over the 17.9 percent protein corn-soybean meal diet. The results of this study indicate that whey-yeast protein is consistently superior to soybean meal protein for baby pigs. The reasons for this are unclear; however, whey-yeast protein contains higher levels of most indispensible amino acids than soybean meal protein. The possibility of whey-yeast lysine being more readily available to the pig than soybean meal lysine is suggested in this study.