Histological changes in the intestine of Channa striatus growouts fed with different fat sources: effects of dietary manipulation

Abstract

In the present study the intestinal sac method (ex vivo) was used to evaluate the interactions between different fats in the diets and the histology of the gastrointestinal (GI) tract of Saul (Channa striatus). Saul was fed with six diets (L3HUF, F1; H3HUF, F2; MUSOL, F3; LINOL, F4; MIXOL, F5; SATOL, F6) and a control (NATFO, F7) with natural food. F1, contains 0.5% -3 fatty acid and 7.5% saturated oil; F2, contains 1.0% -3 fatty acid and 7.0% saturated oil; F3, contains 8.0% mustard oil; F4, contains 8.0% linseed oil; F5, contains 4.0% mustard oil and 4% linseed oil; F6, contains 8% saturated oil. Control and fishes fed with different fat had almost similar cellular appearance to intact intestinal mucosal epithelium, with no signs of prominent cellular damage. However, fishes fed with mustard oil in the diet depicting spaces at the base of the villi; fishes fed with linseed oil showing appearance of spaces between circular muscles and base of villi; fishes fed with mixed oil showing elongated lumen in villi, circular muscles are enlarged and fishes fed with saturated oil showing elongated lumen in villi. The results suggests that supplementation of different fat and/or essential fatty acids has direct relation with the histological changes in the intestinal tissue and observations conceptualize that dietary interventions of lipids in the fish feed has relation with cellular and tissue level modifications in the intestine.