CLDN1 and fetal growth restriction: For colonic mRNA levels of ZO-1, Claudin-1, and Occludin, their expressions were lower (p < 0.05) for the IUGR lambs than for the CON lambs but were increased (p < 0.05) upon the supplementation of Arg or NCG to IUGR lambs compared to the non-supplemented IUGR lambs.