SOD1 and fetal growth restriction: Compared to the IUGR group, dietary added 600 mg Zn/kg from Nano-ZnO significantly lowered the MDA and PC content (P < 0.05) and enhanced the CAT, T-AOC, GSH-Px activity and GSH content (P < 0.05) in the jejunal mucosa of IUGR pigs, but did not significantly alter the T-SOD activity (P > 0.05).