title: Dietary fatty acid composition affects the repeat swimming performance of Atlantic salmon in seawater.
abstract: Repeated critical swimming performance trials (Ucrit) were performed on Atlantic salmon (Salmo salar) to test the null hypothesis that the source of dietary lipids (fish-based, poultry-based, and plant-based) does not influence exercise and recovery performance. Four diets were prepared by extensively replacing supplemental lipid from anchovy oil (AO; 100% AO at 150 g/kg) with cold pressed flaxseed oil (FO; 25% AO, 75% FO), sunflower oil (SO; 25% AO, 75% SO), or poultry fat (PF; 25% AO, 75% PF). These diets had equivalent protein and energy concentrations, but due to the different supplemental lipid sources, varied widely in their fatty acid composition. Fish fed AO had a significantly higher (P<0.05) first Ucrit (2.62+/-0.07 body lenght s(-1)) than those fed PF (2.22+/-0.12 body lenght s(-1)) that had low muscle ratios of n-3 highly unsaturated fatty acids (n-3 HUFA) to saturated fatty acids (SFA) and arachidonic acid (AA), and high levels of oleic acid. Fish in the FO and SO diet groups swam as well as AO-fed fish in both swimming trials. The performance of fish fed AO decreased significantly (P<0.05) during the second swimming trial (i.e. Ucrit2/Ucrit1=0.92+/-0.02). No significant differences occurred between diet groups for the second swim trial. There was a positive correlation between both n-3 HUFA/SFA and n-3 HUFA/AA ratios, and Ucrit1. A negative correlation was found between dietary AA and oleic acids, and Ucrit1. The present study suggests that low dietary n-3 HUFA/ SFA and n-3 HUFA/AA ratios may negatively affect swimming performance. The former possibly can be offset by increasing linoleic acid in the presence of nutritionally adequate n-3 HUFA (e.g. SO diet). Lipid supplements consisting largely of vegetable oils did not compromise fish cardiorespiratory physiology under the conditions of this study.
authors.affiliation: Faculty of Agricultural Science, University of British Columbia, 266B-2357 Main Mall, Vancouver, BC Canada V6T 1Z4. glennw@interchange.ubc.ca
authors.forename: G N
authors.initials: GN
authors.lastname: Wagner
authors.forename: S K
authors.initials: SK
authors.lastname: Balfry
authors.forename: D A
authors.initials: DA
authors.lastname: Higgs
authors.forename: S P
authors.initials: SP
authors.lastname: Lall
authors.forename: A P
authors.initials: AP
authors.lastname: Farrell
mesh_terms: D000818:Animals; D004032:Diet; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology*; D005227:Fatty Acids / Q000737:chemistry* / Q000494:pharmacology; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology; D043371:Fatty Acids, Omega-6 / Q000494:pharmacology; D008055:Lipids / Q000737:chemistry / Q000494:pharmacology; D010805:Physical Conditioning, Animal; D010938:Plant Oils / Q000737:chemistry; D020317:Salmo salar; D012623:Seawater; D000074242:Sunflower Oil
chemical_list: D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D008055:Lipids; D010938:Plant Oils; D000074242:Sunflower Oil