The effect of vegetable and fish oil at different concentrations in genetically male tilapia was evaluated during 90-days trial. Fish were assessed on the basis of five diets with inclusion of 2 % fish oil (FO) for T1, 5 % FO for T2, 2 % linseed oil (LO) for T3, 5% LO for T4 and control. The observed results were significantly different (P < 0.05) among all treated groups in growth performance with best values of net weight gain, specific growth rate, percent weight gain, feed conversion ratio and feed efficiency for fish fed on 5 % LO rather than others. Proximate analysis for both periods showed significant difference (P < 0.05) in between all treated groups that showed similar trends, where crude protein contents were maximum in 2% FO fed feed and crude fat contents were highest in5% LO fed feed. However, fatty acid composition of liver was influenced by dietary treatment and sampling period. The 14:0, 16:0, 18:2 n-6, 18:3 n-3, 20:2 n-6, ∑SFA, ∑PUFA, n-6 and n-3/ n-6 fatty acids showed significantly (p<0.05) different results among all treatments, depending on the source of supplemented oil. EPA, DHA, ∑PUFA and n-6 showed highest values in muscle of fish fed upon 5% LO. Moreover, significant (p<0.05) results were observed in both periods with prominent values of 16:1, 17:1, EPA, ∑PUFA and n-6. These results concluded that linseed oil improved the fatty acid profile without compromising growth performance, feed efficiency and fish health of Tilapia.
Keywords: Specific growth rate, proximate composition, Omega-3, Omega-6 fatty acids,