Computed tomographic and radiologic anatomy of the lower respiratory tract in the red-foot tortoise (Chelonoidis carbonaria)

Abstract

Polanco J.B.A., Mamprim M.J., Silva J.P., Inamassu L.R. & Schimming B.C. 2020. Computed tomographic and radiologic anatomy of the lower respiratory tract in the red-food tortoise (Chelonoids carbonaria). Pesquisa Veterinária Brasileira 40(8):637-646. Departamento de Anatomia, Instituto de Biociências, Universidade Estadual Paulista “Júlio de Mesquita Filho”, Rua Prof. Dr. Antônio Celso Wagner Zanin 250, Distrito de Rubião Junior, Botucatu, SP 18618-689, Brazil. E-mail: bruno.schimming@unesp.br The diagnosis of several diseases in chelonians is a challenge in the veterinary clinic, because a detailed physical examination with auscultation and palpation is difficult due the presence of carapace and plastron. Imaging analysis such as radiography and computed tomography (CT) have been shown to be beneficial for diagnosis, prognosis and treatment in numerous animal species. Thus, this study aimed to identify and describe the structures of the lower respiratory tract in red-foot tortoises, by computed tomography, radiography and gross anatomy in twelve red-foot tortoises (Chelonoidis carbonaria), adults and of both sexes. The lower respiratory tract in these animals comprised the larynx, trachea, bronchi and the lungs. The presence of epiglottic cartilage was not observed in the animals studied. CT allowed the observation of the intrapulmonary part of the bronchi, which was accompanied by large intrapulmonary blood vessels. The lungs presented a reticulated parenchyma, without lobulations. Each lung had a small chamber located near the cranial and caudal poles. These structures were identified in CT and 3D CT reconstructions and these could suggest that these chambers could be non-respiratory structures, and could be comparable to the air sacs of birds. This study establishes normal CT anatomy of the lower respiratory tract of the red-foot tortoise; and may be used as a reference in the assessment of respiratory disorders in this tortoise.