Partial replacement of fish oil by soybean oil on growth performance, survival and fatty acid metabolism in Persian Sturgeon (Acipenser persicus) fingerlings

Abstract

The aim of the study was to investigate the replacement of fish oil by soybean oil and the effects on the growth performance, survival and fatty acid metabolism in Persian sturgeon fingerlings. Three iso-nitrogenous and iso-lipidic experimental diets containing 100% fish oil, 50 and 100% soybean oil were fed to triplicate group of fingerlings (initial weight 210 g). No significant difference was observed in the case of weight gain, specific growth rate, feed conversion ratio and survival (P > 0.05). Fillet fatty acid composition was analyzed and the results showed that fillet fatty acid composition was highly affected by dietary fatty acid profile and the highest accumulation rate of linoleic acid (C18:2n6) and linolenic acid (C18:3n3) was observed in 100% soybean and fish oil respectively. Also feeding 50% soybean oil stimulated elongation and desaturation pathway of C18 PUFA in fingerlings and the highest amount of EPA, DHA arachidonic acid (AA) was observed in this treatment. Data obtained show that replacing fish oil with 100% soybean oil had inhibitory effect on the elongation and desaturation of C18 PUFA and the lowest amount of DHA and AA obtained in fingerlings fillet.