title: Modulation of selenium tissue distribution and selenoprotein expression in Atlantic salmon (Salmo salar L.) fed diets with graded levels of plant ingredients.
abstract: Increased substitution of marine ingredients by terrestrial plant products in aquafeeds has been proven to be suitable for Atlantic salmon farming. However, a reduction in n-3 long-chain PUFA is a consequence of this substitution. In contrast, relatively little attention has been paid to the effects of fishmeal and oil substitution on levels of micronutrients such as Se, considering fish are major sources of this mineral for human consumers. To evaluate the effects of dietary marine ingredient substitution on tissue Se distribution and the expression of Se metabolism and antioxidant enzyme genes, Atlantic salmons were fed three feeds based on commercial formulations with increasing levels of plant proteins (PP) and vegetable oil. Lipid content in flesh did not vary at any sampling point, but it was higher in the liver of 1 kg of fish fed higher PP. Fatty acid content reflected dietary input and was related to oxidation levels (thiobarbituric acid-reactive substances). Liver had the highest Se levels, followed by head kidney, whereas the lowest contents were found in brain and gill. The Se concentration of flesh decreased considerably with high levels of substitution, reducing the added value of fish consumption. Only the brain showed significant differences in glutathione peroxidase, transfer RNA selenocysteine 1-associated protein 1b and superoxide dismutase expression, whereas no significant regulation of Se-related genes was found in liver. Although Se levels in the diets satisfied the essential requirements of salmon, high PP levels led to a reduction in the supply of this essential micronutrient.
authors.affiliation: 1School of Natural Sciences,Institute of Aquaculture,University of Stirling,Stirling FK9 4LA,UK.
authors.forename: Monica B
authors.initials: MB
authors.lastname: Betancor
authors.affiliation: 1School of Natural Sciences,Institute of Aquaculture,University of Stirling,Stirling FK9 4LA,UK.
authors.forename: Thi M C
authors.initials: TM
authors.lastname: Dam
authors.affiliation: 2Biomar Ltd,North Shore Road,Grangemouth FK3 8UL,UK.
authors.forename: James
authors.initials: J
authors.lastname: Walton
authors.affiliation: 3BioMar AS,Havnegata 7,Pirsenteret 3,Trondheim 7010,Norway.
authors.forename: Thea
authors.initials: T
authors.lastname: Morken
authors.affiliation: 2Biomar Ltd,North Shore Road,Grangemouth FK3 8UL,UK.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Campbell
authors.affiliation: 1School of Natural Sciences,Institute of Aquaculture,University of Stirling,Stirling FK9 4LA,UK.
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Tocher
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D000975:Antioxidants / Q000032:analysis; D017756:Aquaculture / Q000379:methods; D001921:Brain / Q000201:enzymology; D004032:Diet / Q000662:veterinary*; D015870:Gene Expression; D005979:Glutathione Peroxidase / Q000032:analysis; D015227:Lipid Peroxidation; D008055:Lipids / Q000032:analysis; D008099:Liver / Q000737:chemistry / Q000201:enzymology; D009132:Muscles / Q000737:chemistry; D009753:Nutritive Value; D010938:Plant Oils / Q000008:administration & dosage; D010940:Plant Proteins / Q000008:administration & dosage; D010945:Plants, Edible; D020317:Salmo salar / Q000254:growth & development / Q000378:metabolism*; D012643:Selenium / Q000032:analysis / Q000493:pharmacokinetics*; D017279:Selenocysteine; D051140:Selenoproteins / Q000235:genetics*; D013482:Superoxide Dismutase / Q000032:analysis; D014018:Tissue Distribution
chemical_list: D000975:Antioxidants; D008055:Lipids; D010938:Plant Oils; D010940:Plant Proteins; D051140:Selenoproteins; D017279:Selenocysteine; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D012643:Selenium
keywords: Atlantic salmon; BHT butylated hydroxytoluene; FAME fatty acid methyl esters; FM fishmeal; FO fish oil; GPX glutathione peroxidase; Gene expression; HV feed with high levels of plant protein/vegetable oil; Human selenium intake; LC-PUFA long-chain PUFA; LV feed with low levels of plant protein/vegetable oil; MV feed with medium levels of plant protein/vegetable oil; PIn peroxidation index; PP plant protein; SECP43 transfer RNA selenocysteine 1-associated protein 1b; SOD superoxide dismutase; Selenium; Selenoproteins; TBARS thiobarbituric acid-reactive substances; VO vegetable oil; cDNA complementary DNA