Morfologia, topografia e irrigação do coração do Tamandua tetradactyla

External macroscopic anatomy of the Bradypus variegatus heart

ABSTRACT The sloth is known for its slow movements and arboreal habits. Most parts of its anatomy need yet to be unveiled, in order to understand the peculiarities that justify its behavior. In this sense, an investigation of the external characteristics of the heart of the three-toed sloth, Bradypus variegatus, was carried out to indicate the shape, the faces, the dimensions, the topography, and the coating of this organ. For this purpose, fifteen corpses destined for dissection and four healthy specimens were used to carry out thorax digital x-ray. Based on the obtained results, it was noticed that the heart of the species in question presents conical shape, situated obliquely in the mediastinum, is displaced to the left and has latero-lateral slight flattening. Among the animals, discrepancies were found in the organ skeletopy, which presents the tapered apex and the base, in which the large vessels can be observed, whose arrangements also proved to be variables. The heart presents faces (right and left), margins (cranial and caudal) and is surrounded by the pericardium, which gives off two ligaments, sternopericardial and phrenico pericardial. Its size is proportional to the age and length of the individual, with measurements, in general, slightly larger in males.

Heart structure and coronary blood supply of the Giant anteater (Myrmecophaga tridactyla)

The structure of the heart and the coronary blood supply of wild mammals, including that of threatened species, are poorly understood. This study set out to describe the heart, aortic arch branching and coronary distribution of Myrmecophaga tridactyla, and to compare it with anatomical descriptions of other Xenarthra given elsewhere. Eight adult giant anteater cadaveric specimens were used in this study. Morphological features of the heart and coronary blood supply were examined using gross dissection as well as latex and cast preparations. The heart lied in the median plane of the thoracic cavity and corresponded to a cone-shape structure with a rounded apex facing left. The internal chambers of the heart comprised the same structures described in other mammals. Two different patterns of coronary blood supply were observed in the giant anteater. Hence, it can be concluded that the three species of Xenarthra share the same heart structure described in other mammals to date. Aortic arch branches and variations in coronary blood supply in this study have been described in carnivores, particularly the cat and the galea. The branching pattern of the coronary artery differed from that of other mammals and may be specific to Myrmecophaga tridactyla. Morphological description of the heart of the giant anteater and comparison with morphological features of other mammals, especially Xenarthra, may assist in phylogenetic analysis and provide significant contributions to clinical anatomy of practical procedures.

Heart anatomy and topography of the common marmoset (Callithrix jacchus Linnaeus, 1758)

INTRODUCTION

The morphological study of wild animals serves as a base for more advanced studies in clinical medicine, surgery, and pathology. Due to an urgent need and demand for professionals specialized in this area, studies of this nature have become indispensable and so the objective of the present study was to describe the heart morphology of Callithrix jacchus.

METHODS

Ten anatomic pieces of common marmoset were used. The hearts were removed and dissected for better visualization and thus to makes a detailed description of the structures of the organ of the C jacchus species.

RESULTS

The C jacchus heart is similar to that of other mammals, with small anatomical modifications such as division of the apex by the interventricular grooves, shallow fossa ovalis, and less salient intervenous tubercle.

CONCLUSIONS

This study may serve as taxonomic base for research and also as a basis for clinical and surgical procedures with the C jacchus.