Banca de QUALIFICAÇÃO: JÚLIA VAZ FEIO

Amazonian birdlife; heart; cardiac skeleton.

In the anatomical evolution, the heart went from a contractile vessel to a single ventricle trabeculated and single atrium, in fish and later more developed in amphibians. In reptiles, there was a partial division between ventricles, and in birds and mammals a heart with complete ventricles. The heart has fibrous rings, which serve to stabilize the ostia against contractile deformation. The cardiac skeleton is composed of connective tissue with interspersed parts of cartilage, mineralized cartilage and bone. Ardea alba, popularly Known as the great white heron, it is the most common heron on the planet. It presents white feathers, yellow beak, black legs and fingers. Acts as a bioindicator of ecosystems. Therefore, this study aimed to describe the cardiac anatomy of the species, generating scientific knowledge about the anatomical particularities of this Amazonian birdlife. For this, 10 specimens of great white heron were used, which died due to run over or natural death, under animal use license SISBIO 23401-8. It took place the opening of the coelomic cavity through a median incision to access the cavitary organs. Before organ extraction, in situ and ex situ photodocumentation took place. Afterwards, the material was fixed in 10% formaldehyde.The tissues were processed for light microscopy. according to the usual protocols, in eosin and hematoxylin, trichrome Gomori and orcein, and the slides were photomicrographed. The species studied, ventral view, presented the heart tilted slightly to the right, brachiocephalic trunks emerging of the aortic arch, emerging from the cardiac base and following through the right antimere. Flow rate at vessels, the right atrium, the coronary sulcus and the cone arteriosus were located in the center; atrium left and ventricles, right and left. In the dorsal view, the vena cava were identified right and left cranial veins, caudal vena cava, pulmonary veins and arteries and the pulmonary trunk.Longitudinally, the developed muscles of the left ventricular wall were observed, with the presence of fleshy trabeculae, delimitation of the atria and ventricles, with evidence of aortic, bicuspid and tricuspid valves, pectiniform muscles, chordae tendineae and muscle papillary, and the half-moon appearance that the right ventricle makes surrounding the left. To the cut transverse, the ostium of the pulmonary trunk was noted, arrangement of the aortic ostium, surrounded by fibrous rings, and atrioventricular ostia. Using optical microscopy, it was possible to define the regions of endocardium, myocardium and pericardium. The endocardium presented Purkinje fibers and in the muscle fibers of the myocardium it was possible to visualize some intercalated discs. The layer divisions of the aorta also stood out, being: tunica intima, tunica media and adventitious tunic. At the cardiac base, structures such as cartilage at the base of valves, valves and fibrous skeleton were also possible to be identified. Differential colors were used to determine the type of cartilage present in the fibrous skeleton, which is, predominantly elastic. Thus, it was possible to define that the great white heron has direction of the aorta different from that found in mammals, but, like other species, also has cardiac cartilage in its heart, however, with the type identified uncommon in literature. In the continuation of the study, immuno- histochemistry, scanning electron microscopy and 3D scanner of the anatomical specimen.