Macroscopic morphology and bronchopulmonary distribution in lungs of Procyon cancrivorus

The raccoon (Procyon cancrivorus) is a wild animal of great ecological importance because it is a seed disperser. Bronchopulmonary segmentation was studied in 4 raccoons, using 10% formaldehyde-fixed lung tissue. Lung lobation in P. cancrivorus follows the same pattern as in domestic carnivorous animals and coatis (four right and two left lobes). The lungs of the raccoon are divided into lobes: cranial, middle, caudal and accessory in right lung and cranial and caudal in left lung. The bronchial tree begins with the right and left primary bronchi, which divide into lobar bronchi, which in turn divide into segmental bronchi. Distribution patterns of lobar bronchi and segmental bronchi vary in quantity and arrangement, between the species studied here and other carnivorous species described in the literature. Therefore, we suggest further studies with a larger number of specimens, allowing a statistical analysis of the data to define the bronchial pattern in raccoons.