Nofima study could influence future salmon feed formulations.
New research from Nofima has highlighted the importance of nutrient interactions in salmon feed, showing that the balance of omega-3 fatty acids, zinc, saturated fat and cholesterol plays a critical role in fish health, growth and product quality.
The study, led by senior scientist Bente Ruyter, found that zinc and the long-chain omega-3 fatty acids EPA and DHA act synergistically to improve skin health, wound healing, bone density and overall resilience in juvenile salmon. High levels of zinc and omega-3 were shown to enhance scale development and growth during the freshwater stage, with omega-3 improving the utilization of zinc.
In trials with larger fish, researchers documented that salmon lost minerals and had lower harvest weights when fed diets with insufficient zinc. Mineralization improved when omega-3 levels were raised and total fat content reduced. The study also found that salmon raised in sea cages under more demanding conditions required higher omega-3 levels than those raised in land-based tanks.
Researchers also pointed to the interaction between cholesterol and saturated fat. While often viewed negatively in human nutrition, these components were found to be important for salmon fillet quality. Fish that received too little saturated fat during growth produced fillets with reduced firmness, weaker red coloration, and greater liquid loss after freezing and thawing.
“For salmon to thrive through the production cycle with good growth, health and fillet quality, they need the right feed,” Ruyter said. “What is exciting about these findings is that the interaction between nutrients plays a key role in the salmon’s adaptability to new production environments.”
The project was funded by the Norwegian Seafood Research Fund (FHF). Research partners included the Institute of Marine Research, the Norwegian University of Life Sciences, UiT The Arctic University of Norway, INRAE in France, the University of Gothenburg, Skretting Aquaculture Innovation, and Biomar.
