Red salmon

Red salmon – genetic effects

Summary

Pale and/or uneven red muscle color in salmon is increasingly reported as a quality problem for Norwegian salmon farming. The red muscle color results from astaxanthin in the feed and it is assumed that changes in feed composition, with increased content of various vegetable raw materials, to some part explain the reduced pigmentation. Pale fillet color and uneven pigmentation are also associated with challenging farming conditions, with increased handling of the fish and stress. Genes involved in pigmentation are now being tested using gene editing (CRISPR / CAS9) in the project “Gene Editing to Innovate Norwegian Breeding Industries” (GeneInnovate) (Research Council project no. 281928). The CRISPR fish provides a unique opportunity to identify and study the mechanisms that are essential for the uptake and retention of astaxanthin. In addition, there is a salmon line that is exclusively selected for extra intense red color that will supplement the experiments with the genetically modified fish. The project’s focus will be on mapping molecular mechanisms that control the uptake, transport and turnover of astaxanthin in salmon. This is basic knowledge that is also necessary to formulate a feed that provides sufficient color intensity and color stability in salmon fillets.

Outcomes and impacts

​The project will improve the understanding of astaxanthin metabolism; which genes are involved and how is the turnover regulated (“molecular pathways” in astaxanthin metabolism). This knowledge can be used by the feed industry to identify feed components that increase or inhibit astaxanthin uptake and it improves the understanding of the interaction between short- / long-term effects of stress, feed and genetics.

CIGENE researchers involved: Dag Inge Våge

Page updated: 30.10.2020