AEI prepress abstract  -  DOI: https://doi.org/10.3354/aei00255

Adding value to ragworms (Hediste diversicolor) through the bioremediation of a super-intensive marine fish farm

Bruna Marques*, Ana Isabel Lillebø, Fernando Ricardo, Cláudia Nunes, Manuel A. Coimbra, Ricardo Calado*

*Email: bruna.marques@ua.pt

ABSTRACT: The aim of this study was to evaluate the potential added value of Hediste diversicolor, cultured for 5-month in sand bed tanks supplied with effluent water from a super-intensive marine fish farm, by comparing their fatty acid (FA) profile with that of wild specimens. Results show that during the experimental period polychaetes increased in biomass ~35 times and their FA profile was significantly different from that of wild specimens. In cultivated specimens the most abundant FA class was that of highly unsaturated FA (HUFA), with eicosapentaenoic acid (EPA, 20:5n-3) being the most well represented FA. Similar percentage (SIMPER) analysis showed an average 20.2% dissimilarity between the FA profile of wild and cultivate specimens, supporting the view that the culture system employed enables the recovery of high value nutrients (e.g. EPA and Docosahexaenoic acid (DHA - 22:6n-3)) from fish feeds into the tissues of H. diversicolor that would otherwise be lost from the production environment. While, the nutritional value of wild ragworms is well-established in marine aquaculture (namely for broodstock maturation diets), the higher level of DHA displayed by the specimens produced under the proposed culture system may grant them a premium market value.