RADIOGRAPHIC THORACIC ANATOMY OF THE RED PANDA (AILURUS FULGENS)

Abstract

The red panda ( Ailurus fulgens ) is classified as an endangered species by the International Union for Conservation of Nature and Natural Resources. The natural distribution of the red panda is in the Himalayas and southern China. Thoracic diseases such as dirofilariasis, hypertrophic cardiomyopathy, tracheal obstruction, lung worm infestation, and pneumonia have been reported in the red panda. The aim of this study was to describe the normal radiographic thoracic anatomy of captive red pandas as a species-specific reference for routine health examinations and clinical cases. Right lateral (RL) and dorsoventral (DV) inspiratory phase views of the thorax were obtained in 11 adult captive red pandas. Measurements were made and ratios calculated to establish reference ranges for the mean vertebral heart score on the RL (8.34 ± 0.25) and DV (8.78 ± 0.34) views and the mean ratios of the caudal vena cava diameter to the vertebral body length above tracheal bifurcation (0.67 ± 0.05) and tracheal diameter to the width of the third rib (2.75 ± 0.24). The majority of animals (10/11) had 14 thoracic vertebrae, except for one animal that had 15 thoracic vertebrae. Rudimentary clavicles were seen in 3/11 animals. The ovoid, oblique cardiac silhouette was more horizontally positioned and elongated in older animals. A redundant aortic arch was seen in the oldest animal. The trachea was seen with mineralized cartilage rings in all animals. The carina was clearly seen in the majority of animals (10/11). Variations exist in the normal radiographic thoracic anatomy of different species. Knowledge of the normal radiographic thoracic anatomy of the red panda should prove useful for routine health examinations and in the diagnosis of thoracic diseases.

Anatomy of the Red Panda (Ailurus fulgens)

“…The spinous processes of the thoracolumbar vertebrae are short ( Figure 2A) (Makungu et al, 2016;Makungu et al, 2018). The size of the thoracic vertebrae increase from cranial to caudal with the thoracic vertebra 11 (T11) frequently being an anticlinal vertebra and rarely T10 (Makungu et al, 2016). Lumbosacral transitional vertebra and the presence of two fused sacral segments have been reported in red pandas (Makungu et al, 2018).…”

“…The vertebral formula of the red panda is 7 cervical, 14 thoracic, 6 lumbar, 3 fused sacral and up to 19 caudal (coccygeal) vertebrae [C7, T14, L6, S3, Cd19] (Flower, 1870;Fisher 2011;Makungu et al, 2016;Makungu et al, 2018). However, it is uncommon to find red pandas with 15 thoracic and 5 lumbar vertebrae (Makungu, 2015).…”

“…Further, 19 thoracolumbar vertebrae have been reported in a red panda with 14 thoracic and five lumbar vertebrae (Makungu, 2015). The spinous processes of the thoracolumbar vertebrae are short ( Figure 2A) (Makungu et al, 2016;Makungu et al, 2018). The size of the thoracic vertebrae increase from cranial to caudal with the thoracic vertebra 11 (T11) frequently being an anticlinal vertebra and rarely T10 (Makungu et al, 2016).…”

“…The number of ribs in red pandas is mainly 14 pairs which correspond to the number of thoracic vertebrae (Figure 2). Of the 14 pairs, the last two pairs are floating ribs ( Figure 2) (Makungu et al, 2016). Pandas with 15 pairs of ribs, the last three pairs are floating (Makungu et al, 2016).…”

“…Of the 14 pairs, the last two pairs are floating ribs ( Figure 2) (Makungu et al, 2016). Pandas with 15 pairs of ribs, the last three pairs are floating (Makungu et al, 2016). The sternum is fairly straight and consists of the manubrium sterni, xiphoid process and six sternebrae ( Figure 2A) (Makungu et al, 2016).…”