Faternal and Maternal Response to High Feed Intake from Day 29 to 45 of Gestation

Kansas State University Swine Research. Parity-four sows were fed either 4.0 lb/d (control, n = 6) or 14.0 lb/d (high, n = 9) of feed from d 29 to 45 of gestation. On d 45 of gestation, sows were slaughtered and uteri collected for fetal and placental measurements. High-feed-intake sows gained more wieght from d 29 to 45 comparted to control sows. Providing feed in excess of established requirements to gestating sows from d 29 to 45 of gestation increased IGF-I concentrations in maternal plasma and decreased crown-rump length variation of the fetus. Increased Feed intake resulted in removal of the correlation between average fetal weight and number of fetuses per sow. We postulate that the increases maternal IGF-I or other maternal responses to high feed intake altred the maternal limit on fetal growth at this stage of gestation.