Segmental aplasia of the trachea in a domestic feline

Abstract

Developmental changes correspond to a heterogeneous group of conditions characterized by morphological and functional malformations of organs that may be of genetic origin, teratogenic factors, infectious agents, chemical substances, physical agents, or nutritional deficiencies. Segmental aplasia of the trachea is a malformation, represented by the absence of tracheal rings, rarely described in animals. The present work describes a malformation in a feline, female, SRD, 1-year-old, which presented slightly hypocolored mucous membranes, moderate dehydration, mild dyspnea, and, after death, was sent for necropsy. Macroscopically, in the distal portion of the trachea, in the region of the tracheal bifurcation, and involving the initial portion of primary bronchi, there was a segmental area of approximately 4.2 centimeters in length, in which there were no cartilaginous semi-rings. Microscopically, small plates of juxtaposed hyaline cartilage were observed at the beginning of this region, forming a disorganized semi-ring delimited by an immature loose connective tissue and a well-differentiated unilocular adipose tissue. Based on the anatomy-histopathological changes, the diagnosis of distal segmental aplasia of the trachea and the initial portion of the primary bronchi bilaterally was established.