Structural arrangement of the cardiac collagen fibers of healthy and diabetic dogs.

The heart is composed by a specialized muscle, whose form and function are essentials for an adequate work and shows an amount of connective tissue which support and provide insertion for this muscle, whose collagen fibers are responsible for determination of tissue feature. Our objective was to identify the structural arrangement of the heart collagen fibers in dogs. The hearts of the dogs were submitted to the process of the controlled digestion with NaOH solution and observed by scanning electron microscope.

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.