Numerous recent studies showed changes in gene expression of proteins are responsible for intestinal tight junction integrity or barrier function (claudin-1, occludin, mucin-2, Fatty acid-binding protein-2) in broiler chickens during gut inflammation induced by C. perfringens challenge, which are similar to those observed in humans during the IBD [47,48,49,50]. Here, CLDN1 is linked to inflammatory bowel disease.