Toward Improved Public Confidence in Farmed Fish Quality: A Canadian Perspective on the Consequences of Diet Selection

Marine fish oils (MFO) are used in salmon diets to mimic the natural diet, to ensure that essential fatty acid requirements for good fish growth and health are met, and to provide salmon flesh with an omega-3 highly unsaturated fatty acid content that can benefit human health. However, an extensive use of MFO in formulated salmonid diets is perceived as an unsustainable use of wild marine fish stocks. In addition, MFOs have a background level of persistent organic pollutants (POPs) unrelated to aquaculture practices. This review considers recently completed studies using alternative lipid sources of terrestrial origin as replacements for MFO and shows that the composition of conventional finfish diets can be altered to reduce the reliance on MFO while concurrently maintaining fish health as well as reducing background levels of POPs. A challenge still ahead is the need for a concerted and sustained outreach to ensure that the public is aware of such improvements to seafood quality so that the preoccupation of the news media with presenting negative images of fish culture to the public is combated.