By Erich Luening
Norwegian research has shown that some salmon families have higher levels of healthy fatty acids in their muscle tissue than others.
From cancer prevention to promoting infant health and development and inhibiting cardio vascular disease, essential Omega 3 fatty acids have proven to be nutrient behemoths in human health, and researchers in Norway believe they can raise salmon bred to be teaming with the essential fatty acids.
However, over the last decade the level of these fatty acids in farmed salmon fillets has decreased owing to the substitution of fish oil with vegetable oil in the fish feed. Fortunately, salmon have the capacity to convert fatty acids from plants into EPA and DHA, according to researchers at Norwegian breeding and genetics giant Nofima AS.
While feed is the largest factor determining the level of EPA and DHA in the fillet, there is evidence that genetics also plays a role. Previous research has shown that some salmon families have higher levels of the healthy fatty acids in their muscle tissue than others, suggesting there is potential in using selective breeding as a tool to increase levels of omega-3 in Atlantic salmon muscle.
“Our research has shown that the individual omega-3 fatty acids have different heritability, as well as different correlations to other important production traits,” said Siri Storteig Horn, a PhD researcher at Nofima conducting the research. “All the major fatty acids in the muscle showed a certain degree of heritability. DHA was the omega-3 fatty acid with the highest heritability (0.26), proving to be the best trait for selection. EPA had a low heritability (0.09).”
Horn said that they’ve estimated the heritability of individual omega-3 fatty acids and their relationships to lipid deposition traits and other traits of the breeding goals (carcass, quality and disease).
“This is key to predicting the consequences of selection for higher levels of healthy omega-3, and is important information for breeders if they want to implement selection for this trait,” she added.
Currently Horn is working on identifying the genes associated with increased omega-3 content in salmon muscle.
“This will increase the understanding of the biological processes underlying the trait, as well as improve selection accuracy by allowing marker-based selection,” she said.
Should this prove viable, salmon breeders can implement marker-based selection for healthy omega-3 and produce a salmon with higher nutritional value to consumers.
Ultimately, Nofima wants to see if it is possible to increase the salmon’s natural capacity to convert short-chained omega-3 form plant oil into EPA and DHA through selective breeding, and in this way stop the decline in omega-3 levels in farmed salmon fillets.
To achieve this, they’re aiming at increasing the understanding of which biological processes are determining the level of healthy omega-3 fatty acids in salmon muscle.
Horn said breeding and genetics is at the very foundation of successful salmon farming and will continue to meet future challenges facing the industry.