Melanin spots are a growing concern in the salmon farming industry, affecting up to 30 percent of fish in some regions and leading to product downgrades, reduced yields and increased processing costs.
The spots, which are visible in the fillets, are the result of the fish’s immune response to inflammation caused by stress or tissue damage.
Research by Aker BioMarine shows that including its krill-based QRILL Aqua, which contains high levels of omega-3 fatty acids into feeds can effectively prevent accumulation of melanin pigments and improve fillet quality.
If fish are subject to injury or stress, such as hypoxia or trauma, dark melanin pigments appear on the fillet. Dealing with these spots requires the removal of affected areas, which increases labour costs and at times can lead to the complete discarding of fillets. In Norway alone, as much as 20 percent of harvested salmon is impacted, while in Chile, melanin spots are responsible for nearly 30 percent of downgrades, according to Aquabench.
Chronic inflammation is a major factor in the development of melanin spots. Omega-3 fatty acids, specifically EPA and DHA, are essential for regulating inflammation and preventing chronic condition. According to Aker BioMarine, its internal research trials demonstrate that including 7.5 percent QRILL Aqua in salmon diets can eliminate melanin spots in fish between 1.2 to 3.2 kg, as it delivers these fatty acids in a phospholipid form that is more easily absorbed by fish.
This is supported by other recent studies, including the EX-spot 2022 report, which confirm that increasing EPA and DHA levels in salmon feeds significantly reduces the severity of melanin spots.