Compared to the CON group, the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), reduced glutathione (GSH) activities, and GSH/oxidized glutathione (GSSG) ratio were lower (p < 0.05), whereas the ROS production and levels of malondialdehyde (MDA), glutathione reductase (GR), hydrogen peroxide (H2O2), and protein carbonyl were higher (p < 0.05) in the colon of IUGR lambs (Supplementary Table S3). The gene discussed is GSR; the disease is fetal growth restriction.