Caracterização morfohistológica do trato digestório de Cichlasoma orientale (osteichthyes: cichlidae)

Abstract

This study used 07 specimens of Cichlasoma orientale, in order to characterize morfohistologicamente the digestive tract of this species. The bucofaringeana cavity of this fish was investigated by means of magnifying glass and scanning electron microscope and exhibited characteristics as terminal mouth with protractibilidade, smooth lips and the upper thinner than the lower lip, triangular and pigmented tongue, rounded jaw with palatine folds, breathing valve and dentigerous plates with conical teeth. In the pharynx highlights the presence of two plates with tapered indentations dentigerous, the tracks are shown shorter, only the first brachial arch and exclusively present in young animals. Technical HEHarris hematoxylin staining, eosin and Periodic Schiff were used to characterize morphologically the layers of the digestive tract with the aid of optical microscope. The esophagus is short with folds mucosa lined by pseudostratified epithelium with mucosecretora cells that are interspersed with nonsecretory cells. The esophageal muscle layer is thick with predominance of striated skeletal muscle fibers which can be evidenced even close to the stomach. These features are probably involved the swallowing habit largest and protection prey. The stomach has format in Y having three regions, all overlaid by a simple epithelium and probably absorptive. The cardial without muscular layer of mucosa with glandular lamina propria; the fundus with many folds mucosa, muscular thin mucous and lot of gastric glands; Finally the pyloric gland and is also thicker muscle layer when compared to other regions. The stomach morphological characteristics indicate a specialized stomach chemistry, acid and protein digestion. The intestine presents itself, anatomically, with two short bowel loops with three anterior, middle and posterior distinct. The layer of the mucosa, the intestinal epithelium throughout, it has a single cylindrical type coating observing goblet cells and enterocytes, villi are also present. The Board is fully responsible aglandular and probably more intensely with the absorption and intestinal digestion possibly dependent hepatopancreáticas secretions. The morphology identified in Cichlasoma orientale presents organs adapted to the omnivorous eating habits to feed the carnivorous trend.