Dietary Linseed Oil Reduces Growth While Differentially Impacting LC-PUFA Synthesis and Accretion into Tissues in Eurasian Perch (Perca fluviatilis).
The aim of this study was to evaluate the impact of replacing dietary fish oil (FO) with linseed oil (LO) on growth, fatty acid composition and regulation of lipid metabolism in Eurasian perch (Perca fluviatilis) juveniles. Fish (17.5 g initial body weight) were fed isoproteic and isoenergetic diets containing 116 g/kg of lipid for 10 weeks. Fish fed the LO diet displayed lower growth rates and lower levels of DHA in the liver and muscle than fish fed the FO diet, while mortality was not affected by dietary treatment. However, DHA content recorded in the liver and muscle of fish fed the LO diet remained relatively high, despite a weight gain of 134 % and a reduced dietary level of long-chain polyunsaturated fatty acids (LC-PUFA), suggesting endogenous LC-PUFA biosynthesis. This was supported by the higher amounts of pathway intermediates, including 18:4n-3, 20:3n-3, 20:4n-3, 18:3n-6 and 20:3n-6, recorded in the liver of fish fed the LO diet in comparison with those fed the FO diet. However, fads2 and elovl5 gene expression and FADS2 enzyme activity were comparable between the two groups. Similarly, the expression of genes involved in eicosanoid synthesis was not modulated by dietary LO. Thus, the present study demonstrated that in fish fed LO for 10 weeks, growth was reduced but DHA levels in tissues were largely maintained compared to fish fed FO, suggesting a physiologically relevant rate of endogenous LC-PUFA biosynthesis capacity.
['Geay|F|F|', 'Wenon|D|D|', 'Mellery|J|J|', 'Tinti|E|E|', 'Mandiki|S N M|SN|', 'Tocher|D R|DR|', 'Debier|C|C|', 'Larondelle|Y|Y|', 'Kestemont|P|P|']
D000123:Acetyltransferases D000818:Animals D017756:Aquaculture D004032:Diet D004042:Dietary Fats, Unsaturated D044943:Fatty Acid Desaturases D000081031:Fatty Acid Elongases D015525:Fatty Acids, Omega-3 D043371:Fatty Acids, Omega-6 D005395:Fish Oils D029941:Fish Proteins D005602:France D018507:Gene Expression Regulation, Developmental D008043:Linseed Oil D050356:Lipid Metabolism D008099:Liver D018482:Muscle, Skeletal D010471:Perches D017747:Seafood D016019:Survival Analysis D015430:Weight Gain
LC-PUFA Eurasian perch FADS2 Eicosanoid Fatty acid metabolism