Radiography and computed tomography of the heart and lower respiratory tract in toco toucans (Ramphastos toco)

Abstract

This study aimed to evaluate normal features of the heart and lower respiratory tract in toco toucans by means of radiography and helical computed tomography (CT) scanner. Fifteen healthy adult toco toucans (Ramphastos toco), 10 females and 5 males, average body mass of 650 g were studied. CT examination as well as right lateral and ventrodorsal radiographic examinations of the coelomic cavity were performed under chemical restraint. Heart, lungs, air sacs, trachea and syrinx were analysed. The mean values of heart length, heart width and thoracic cavity in radiographs were, respectively, 23.76 mm, 25.94 mm and 48.87 mm. In both X‐rays and CT scans, the lung parenchyma had honeycomb‐like pattern. The topographic areas of the anterior and posterior air sacs were visualized as dark and air‐filled spaces in X‐rays. On CT evaluation, the air sacs occupied a larger area in the coelomic cavity compared to X‐ray. In the lateral radiographic view, the cervical part of the trachea was positioned more ventrally in the transition from cervical to thoracic regions showing a V‐shaped appearance. In all CT planes was visible division of the trachea into the right and left main bronchi at the level of 3rd thoracic vertebra. The syrinx was difficult to visualize in X‐rays, but on CT it was easily identified in axial slice. In conclusion, the normal features of toco toucan's heart and lower respiratory tract that were determined on X‐rays and CT scans are useful to compare with sick toco toucans, as well as other bird species.

A Cadaveric Study Using Anatomical Cross-Section and Computed Tomography for the Coelomic Cavity in Juvenile Cory’s Shearwater (Aves, Procellariidae, Calonectris borealis)

“…To the best of the authors’ knowledge, no reports have become available concerning the anatomy of Cory’s Shearwater’s coelomic cavity using advanced imaging diagnostic techniques. Nonetheless, these techniques have been applied to other bird species routinely seen by specialists in the field, such as the domestic pigeon ( Columba livia domestica ), toco toucans ( Ramphastos toco ), and gray parrot ( Psittacus erithacus ), demonstrating that they are essential for enabling normal anatomy and abnormalities in the internal organs of birds [ 20 , 23 , 24 ]. Traditionally, clinicians have used imaging modalities such as radiography [ 30 ] and ultrasonography (usually mode B) [ 16 , 27 ], which have been essential in obtaining images of the bony and the architecture of the internal organs that compose this region.…”

“…Despite all these advantages, there are also notable drawbacks, including the excessive cost of this equipment, the relatively high cost of the procedure, the need to sedate and possibly restrain the bird, and the longer examination time in the case of MRI. In consequence, their use is valuable only in those cases where it is specifically indicated or for remarkable birds such as breeding and falconry birds [ 8 , 20 ]. Due to these shortcomings, traditional diagnostic imaging techniques are still the most routinely used because they are fast, low-cost, and widely available in daily avian practice.…”

“…However, due to the wide interval between slices employed in this study, some structures were not clearly discernible in the transverse and dorsal CT images using different windows. Comparable investigations conducted in other exotic species, such as rabbits, guinea pigs, iguanas, loggerhead turtles, and sea birds, have consistently demonstrated that this combination is essential to anatomical studies based on regions or divisions and in visualizing the relations between various organs [ 11 , 15 , 17 , 20 , 23 , 31 , 32 ].…”

“…These modern techniques enable the acquisition of high-resolution three-dimensional images with minimal distortion and even allow for simulations of dynamic processes within different organs, vascular structures, and nerves, all achieved through a minimally invasive approach. A plethora of investigations exist concerning the application of diagnostic imaging to exotic species [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. However, to our knowledge, a dearth of studies address the anatomical characteristics of the avian coelom utilizing Cory’s Shearwater as a model organism.…”

Computed tomographic and magnetic resonance imaging anatomy of the coelomic cavity in market‐age commercial Pekin Ducks (Anas platyrhynchos domesticus)

“…are only a few published articles describing CT attenuation values of a limited number of avian organs in the coelomic cavity including the lung in toco toucans and the liver, ventriculus, kidney, spleen, intestine, lung, air sacs, testicle and ovary in pet parrots(da Silva et al, 2020;Veladiano et al, 2016b). In the current study, CT attenuation values of multiple intra-and extra-coelomic organs were measured including thymus, thyroid glands, gallbladder, liver, spleen, pancreas, ventriculus, kidneys, adrenal glands, glycogen body, reproductive organs (such as testes and ovaries) and uropygial glands.The CT attenuation values of the airway were not evaluated due to post-mortem changes present in the cadavers.…”