Genetic means of boosting omega-3s in salmon

Some salmon are better able to systhesise the long chain omega-3s EPA and DHA than others, according to new research which could have major impacts on the quality of farmed fish.

The research is part of the project “Genomics of omega-3 in Atlantic salmon”, a four-year NOK 10 million project funded by the Research Council of Norway, with project partners including SalmoBreed, the University of Southampton, Nofima and The Norwegian University of Life Sciences (NMBU).

If successful it could help to boost the omega-3 content in farmed salmon, despite the declining marine content in their feeds.

The current element is being undertaken by doctoral student Siri Storteig Horn, at Nofima, who has studied the heritability of individual fatty acid synthesis in the SalmoBreed breeding population. She has found major differences.

“The main marine omega-3 fatty acids in salmon are EPA and DHA. Our findings show that the muscle content of EPA has low heritability, while DHA has quite high heritability, estimated at 26%.

In other words, genes determine 26% of the variation in fatty acid content in muscle tissue, meaning there is great potential in increasing this fatty acid through selective breeding. The results also indicated that a fish that has a high level of EPA does not necessarily have a high level of DHA,” says Horn.