Histological Approach of the Digestive Tract in The Digestibility of Prey in Hepsetus akawo (Characiforms, Hepsetidae) in the Hydroelectric Dam Lake of Ayame 1 (Ivory Coast)

The present work aims to know the digestibility of the prey that make up the diet of Hepsetus akawo fish from monthly catches in the Ayame 1 hydroelectric dam lake. In order to provide information, the digestibility of prey, the stomach contents of 286 specimens, coupled with the histology of digestive tract were analyzed from July 2021 to June 2022. The observation and description of the digestive tract in this species revealed a developed stomach and relatively short intestine. The intestinal coefficient of between 0.94 and 1.68 made it possible to classify the species in category of Omnivorous fish. Stomach contents were analyzed using the corrected percent occurrence, weight percent and dietary index methods. It appears from this analysis that the species Hepsetus akawo was an Omnivore with an insectivorous tendency. Microscopically, the different areas of the digestive tract were made up of four distinct tunics, the serosa, the muscular, the sub-mucosa and the mucosa, the structure and physiology of which differ depending on the areas. The tunics of the esophageal zone contribute to its distension, those of the stomach participate in chemical and mechanical transformations of the prey, with the intestinal layers involved in the absorption of nutrients. Insects with soft cuticles were more digestible and nutrients were easily absorbed, which improves the body condition of fish in the wild or farms.Subject AreasCell Biology, Histology