Journal article · Ahead of Print article
Growth performance, bioavailability of toxic and essential elements and nutrients, and biofortification of iodine of rainbow trout (Onchorynchus mykiss) fed blends with sugar kelp (Saccharina latissima)
Research Group for Analytical Food Chemistry, National Food Institute, Technical University of Denmark1
National Food Institute, Technical University of Denmark2
Research group for Nano-Bio Science, National Food Institute, Technical University of Denmark3
University of Porto4
SPAROS Lda.5
TARALAKS AS6
The Portuguese Institute for Sea and Atmosphere7
National Institute of Aquatic Resources, Technical University of Denmark8
Aquaculture production is demanding novel feed ingredients that reflect natural marine nutrient levels, that are also essential to humans. In this regard, biofortification through addition of iodine-rich sugar kelp in feed formulations was assessed in a 12 week rainbow trout trial. Yttrium inclusion in feed allowed determinations of apparent absorption coefficients of essential and potentially toxic elements and apparent digestibility coefficient of nutrients.
E.g. apparent absorption coefficients in trouts fortified feed with 1–4% dw kelp were 67–61% As, 32–40% Cd, <5% Fe; 80–83% I; 66-58% Se. Iodine concentrations in feed up to 239 mg/kg (∼4% kelp) was proportional to iodine accumulation in trout fillets (R2 = 1.00) with 0.5% transfer ratio. Feed iodine concentrations up to 117 mg/kg (∼2% kelp) did not affect growth performance negatively, but increased significantly protein efficiency ratio after eight weeks feeding.
However, 4% kelp meal inclusion affected final growth and hepato somatic index, and caused histomorphological changes in the intestine. All fillets had low toxic element concentrations (As, Cd, Hg, Pb). The potential applicability of Saccharina latissima as feed ingredient to tailor iodine concentration in farmed fish is evident.
Consuming of a 160 g fillet (2% kelp) contributes ∼60% of recommended daily iodine intake for adults.
Language: | English |
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Year: | 2020 |
Pages: | 111387 |
ISSN: | 18736351 and 02786915 |
Types: | Journal article and Ahead of Print article |
DOI: | 10.1016/j.fct.2020.111387 |
ORCIDs: | Granby, Kit , Amlund, Heidi and Sloth, Jens Jørgen |
Apparent absorption coefficient Arsenic Digestibility Iodine biofortification Macroalgae Rainbow trout SDG 14 - Life Below Water
Animal Feed Animals Biological Availability Iodine Oncorhynchus mykiss Phaeophyceae