The results showed that immunoglobulin (IgA, IgM, and IgG) and antioxidant–related enzymes (MDA, T–AOC, CAT, GSH–Px, and T–SOD) in the serum of crossbred offspring (CAH and CDH) lambs did not differ from those of H lambs (p > 0.05). This evidence concerns the gene CD40LG and congenital diaphragmatic hernia.