Distribution of collagen fibers in the aggregated lymphoid follicles of swine terminal ileum.

The arrangement of the collagen bundles was studied in the Peyer's patches of swine terminal ileum, by means of light microscopy (using silver-impregnation technique and picrosirius F3BA staining) and scanning electron microscopy (after NaOH-maceration). The lymphoid tissue forms a large and continuous patch along the antimesenteric border. The follicles are disposed mainly in the tela submucosa and sometimes they reached in the tunica mucosa surface (follicle/dome structures).

The frenula of the papilla ilealis of the swine.

The junction between the small and the large intestines has been studied in several animals since this region makes an important intestinal transition. Like humans the swine have a structure that forms a boundary between the cecum and the ascending colon - the frenulum papillae ilealis dorsalis and ventralis. Nevertheless the morphology and physiology of this is poorly known.