Histological Study of the Digestive System in Different Stages of Development of Pacu (Piaractus brachypomus)

Abstract

Pacu (Piaractus brachypomus) is the second source of fish production in Colombia after the red tilapia (Oreochomi ssp.) and before the rainbow trout (Oncorhynchus mykiss). It also stands out as one of the species with the most productive potential in the country. A histological examination was performed on the digestive system of the Piaractu sbrachypomus in order to determine normal morphology at different stages of development. For that purpose, the animals were classified according to age, size and weight in fertilized eggs, yolk-sac larvae, fingerlings after yolk-sac reabsorption, young (3-5 cm, 5-7 cm, 10 cm, 15 cm) and adults (300 g). Tissue fixation took place in formaldehyde at 3.7 % and the oral cavity, pharynx, esophagus, stomach, pyloric caeca, intestines and related glands, liver and pancreas were microscopically described. Finally, the anatomical organization of this system was macroscopically described.