Microscopic characterization of esophageal regions of a group of Capybara (Hydrochoerus hydrochaeris) free in Brazil

Morphological studies on wildlife animals have increased in an attempt to explore and understand minutely their adaptive evolution and how it relates to or differentiate from domestic animals. The aim of this study was to describe microscopically esophageal regions (cranial, middle and caudal) of a group of male and female capybaras, using histological techniques. Samples were harvested, fixed, processed and analyzed. All three esophageal regions were covered by keratinized stratified epithelium, thicker in folds apex and towards the caudal region, proximal to the stomach. In this layer, stratum granulosum was well developed. The submucosa, constituted of Loose connective tissue, showed no glands. The muscular layer, externally lined by serous and/or adventitial layer, presented two orientations (circular and longitudinal) in the three regions, and it showed striated skeletal muscle fibers with developed nerve plexus.