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An extended feeding history with a stearidonic acid enriched diet from parr to smolt increases n-3 long-chain polyunsaturated fatty acids biosyntheses in white muscle and liver of atlantic salmon (Salmo salar L.)
journal contribution
posted on 2023-05-17, 09:18 authored by Mohamed CodabaccusMohamed Codabaccus, Andrew BridleAndrew Bridle, Nichols, PD, Christopher CarterChristopher CarterVegetable oils (VO) are globally accepted alternatives for fish oil (FO) in aquafeeds. The lack of n-3 long-chain (≥C20) polyunsaturated fatty acids (n-3 LC-PUFA) in VO is a major constraint. Echium oil (EO), rich in stearidonic acid (SDA), has the potential to increase endogeneous n-3 LC-PUFA biosynthesis. We tested whether feeding Atlantic salmon an EO-based diet in both freshwater and seawater would increase n-3 LC-PUFA levels by comparing the fatty acid (FA) profiles in liver and white muscle to fish fed FO and rapeseed oil (RO)-based diets. The gene expression of n-3 LC-PUFA biosynthetic enzymes was measured to demonstrate the underlying mechanism of n-3 LC-PUFA biosynthesis. After prolonged feeding with EO diet from freshwater to seawater phases, EO fish had higher n-3 LC-PUFA levels in both liver and white muscle compared to RO fish. However, FO fish had the highest n-3 LC-PUFA levels in examined tissues. Δ6 Desaturase gene expression in liver and white muscle was up-regulated in RO fish only, liver Δ5 desaturase gene expression was reduced in seawater and liver FA elongase gene expression was regulated by an interaction between dietary oil and environment. This study showed that feeding Atlantic salmon from parr to smolt using an SDA enriched diet increases n-3 LC-PUFA biosynthesis in liver and white muscle through increased supply of the n-3 LC-PUFA precursor SDA. The down regulation of Δ5 desaturase gene expression in the liver of seawater fish may explain environmental differences in n-3 LC-PUFA biosynthesis
History
Publication title
Aquaculture: An International Journal Devoted to Fundamental Aquatic Food ResourcesVolume
322-323Issue
DecemberPagination
65-73ISSN
0044-8486Department/School
Institute for Marine and Antarctic StudiesPublisher
Elsevier Science BvPlace of publication
Po Box 211, Amsterdam, Netherlands, 1000 AeRights statement
The definitive version is available at http://www.sciencedirect.comRepository Status
- Restricted