IUGR also significantly reduced serum glucose and lactase levels (p < 0.05) while significantly increasing mRNA levels of jejunal IRE1α, EIF2α, CHOP, Bax, Caspase9, Mucin2, Claudin-1, Occludin, ZO-1, Bcl-2, IL-6, and IFN-γ (p < 0.05), as well as GRP78 protein levels in neonatal piglets (p < 0.05). This evidence concerns the gene CLDN1 and fetal growth restriction.