Morphological study of the respiratory system of the brown-nosed coati (Nasua nasua)

Abstract

The goal of this study was to describe, macroscopically and with light microscopy, the respiratory organs of the brown-nosed coati (Nasua nasua). Five animals were euthanized, fixed in 10% formaldehyde solution and stored for dissection. The respiratory tracts of the coati were examined, measured and photographed. For the light microscopy study, fragments were collected from the respiratory organs, processed using standard techniques for histology and stained with HE and toluidine blue. The nose of the coati is pointed and turned upward. Internally it has ethmoidal, dorsal nasal and ventral nasal conchae that are separated by the dorsal and ventral nasal meatuses. The larynx has four cartilaginous structures: arytenoid, cricoid, epiglottis and thyroid. The trachea contains 34 tracheal rings and tracheal ligaments that are covered with ciliated pseudostratified epithelial tissue. The lungs are divided into lobes by interlobular fissures. The right lung is divided into four lobes and is larger than the left lung, whereas the left lung has only two lobes. Microscopically, the primary, secondary and tertiary bronchi have epithelial tissue that is similar to the trachea. We conclude that the respiratory tract of the brown-nosed coati resembles the respiratory tracts described for domestic carnivores.

Keywords

• Coati
• Morphology
• Respiratory