Scientists at the Nofima research institute in Norway have been investigating whether salmon families differ in their ability to convert omega-3 from plant oils to marine omega-3 fatty acids.
Salmon were selected on the basis of a single gene – the gene that controls the production of an enzyme known as delta-6-desaturase. This enzyme is known to be a key element in the conversion of plant omega-3 to marine omega-3 fatty acids. Nofima had carried out its own preliminary studies in selecting for this particular gene, and the research institute has used information stored in gene banks which store gene sequences.
The experiments were started after a single generation of salmon families from breeding company SalmoBreed had been subject to selection. Salmon with a high or a low expression of delta-6-desaturase were selected as parents, and their offspring were tested in the experiments.
Offspring from salmon selected for a high expression of the gene had a higher capacity for producing omega-3 fatty acids than offspring from salmon with a low expression of the gene.
“Our studies of gene expression and fatty acid composition have confirmed that several factors affect the ability of salmon to convert omega-3 fatty acids. These factors include light cycling, transfer to seawater, the age of the salmon, and their genetic background,” says Nofima scientist Tone-Kari Knutsdatter Østbye.
The project was carried out as a collaboration between Nofima, SalmoBreed and Biomar. The experiments were carried out at Nofima’s research station in Sunndalsøra, Norway.