Arabian Oryx (Oryx leucoryx) Trachea: a Descriptive and Morphometric Analysis

Abstract

The objective of this study was to report the distinctive anatomical and histological features of the trachea of the Arabian Oryx (Oryx leucoryx). The number of tracheal rings and tracheal length were measured. The diameter, thickness and cross sectional area of tracheal ring were determined at four tracheal regions (cranial cervical (CCR), middle cervical, thoracic inlets and intra thoracic). Tracheal rings were also collected for histological analysis. The mean length of the trachea was 54.1cm ± 0.73, while the number of tracheal rings varied from 50-51. Tracheal ring measurements (diameter, thickness and cross sectional area) were smallest at the thoracic inlet region. The ratio of the outer transverse to outer vertical and inner transverse to inner vertical diameter ranged between 0.75 and 0.98. The histological analysis revealed that the wall of the trachea consists from four histological layers: a mucosa made of pseudostratified epithelium and lamina propria, submucosa made of dense irregular connective tissue, a hyaline cartilage and a tunica adventitia made of loose connective tissue.