76 Awardee Talk: Maternal Immune Activation Impacts Offspring Immune Function but not Muscle

Abstract Gestational health challenges may influence growth performance and immunity of offspring pigs during postnatal life. In particular, porcine reproductive respiratory syndrome virus (PRRSV) is endemic in the U.S. herd, but its effects on surviving piglets are largely unknown. Further, dietary supplementation with soy isoflavones lessened severity PRRSV infections weaning growing pigs. Therefore, goals this study were to determine impact maternal infection muscle immune development potential mitigate those effects. Thirteen first parity gilts randomly allotted 1 3 treatments: fed a diet devoid not infected (CON), control (POS), supplemented 1,500-ppm (ISF). Isoflavone reduced (P = 0.04) viral load dams 21d after infection, did alter > 0.05) feed disappearance rectal temperature. Piglet mortality was increased by dams, throughout study. Interestingly, organ weights different among treatments at d (PND) exception relative liver weight which POS compared CON, ISF being intermediate. Infected litters lighter 0.02) PND 21, likely due infection. 21 < 0.01) CON POS. Muscle fiber number size differ between ≥ 0.39). Piglets born had slower responses innate stimulation also shifts T cell populations ≤ 0.02), indicating an inadequate vaccine response. Overall, altered development. these