Traditionally, the nutrient requirements of fish were defined on the basis of growth and mortality. Today, the nutrient requirements are increasingly defined so that it ensures fish health and welfare and that the fish produced are robust, i.e. that they do not develop production disorders and can withstand infection pressure in the form of viruses, bacteria, and parasites and that they can cope with various environmental challenges.
Stress can weaken the fish’s immune system. Farmed fish can be exposed to stress, for example in the form of changes in temperature, crowded cages and incorrect nutrition. Fish cope better with stress if they are given optimal feed that covers all their nutrient requirements. NIFES investigate the requirement of individual nutrients and nutrient cocktails for the fish to make them robust.