3.3. Fish fillet fatty acid composition
The fatty acid profile of fish fillet reflected the diet composition and was significantly affected by the lipid source (Table 6).
At the end of the experiment, fish fed the FM100 diet contained less total LC-PUFA, whereas fish from the FM60 and FM20 treatments retained the highest levels, particularly of DHA, which was the dominant n−3 fatty acid.
On the other hand, medium-chain polyunsaturated fatty acid (MC-PUFA) content in fish from the FM20, FM60 and FM80 treatments was significantly lower than that of the Control fed fish.
Concentrations of EPA in fish fillets decreased with increased dietary content of the algal meal from S. limacinum.
These differences resulted in an increase of the DHA:EPA and n−3:n−6 ratios in fish fillet with increasing FO replacement.