Anatomo-histopathological alterations of gastric lesions in free-living giant anteaters (Mymercophaga tridactyla) and lesser anteaters (Tamandua tetradactyla).

Abstract

Abstract The aim of this study was to describe and characterize the anatomo-histopathological alterations observed in the stomach of free-living giant anteaters (Mymercophaga tridactyla) and lesser anteaters (Tamandua tetradactyla). Twenty-two free-ranging anteaters found dead on highways in the state of Mato Grosso do Sul were included. In macroscopy, erosions, ulcers, parasitism and changes in tissue consistency and texture were evaluated, and in microscopy, the intensity and distribution of fibrosis, hemorrhage, necrosis, inflammation and cellular composition. The mucosa was the most affected layer, predominating gastritis as the main lesion, occurring in all portions of the stomach, with the cardia being the most injured region and most sensitive to aggressions. The presence and severity of the lesions were better evidenced by microscopy. The lesions showed characteristics of chronicity. Gastritis occurred in 100% of the samples, predominantly mixed composition, with mild intensity and diffuse distribution. Parasites were observed in five stomachs accompanied by granulomatous and eosinophilic inflammation: moderate in three, mild in one and severe in one. The slight response to parasites demonstrated that anteaters have high tolerance and adaptation to parasitism. The most frequently found helminths were adults and larvae of the genus Physaloptera. All anteaters in this study were found with evidence of being victims of vehicular collisions, demonstrating the fragility of these specimens in the face of anthropogenic action.