Feed Used in Aquaculture

Farmed salmon, like other farmed fish, are fed dry pellets produced using either steam pelleting or extrusion technology. The feed is formulated to meet the nutritional requirement of the fish at every life stage to ensure rapid growth and optimum health. Fish feed contains a variety of ingredients, including fishmeal and fish oil, and other ingredients of animal, vegetable and microbial origin commonly used to feed all types of domestic animals.

The feed used in Canada’s aquaculture industry has become significantly more sustainable over the last decade. In part because we have a wide variety of ingredients available, Canada has become a world leader in feed research that allows increasing use of alternate ingredients. This has significantly reduced dependence on the limited global supplies of fishmeal and fish oil making aquaculture much more sustainable both economically and environmentally.

Fishmeal and fish oil are globally traded commodities whose prices have been increasing as demand grows from all users. Using feed efficiently benefits both the farmer and the environment.

Minimizing environmental impact

Marine and freshwater environments have capacity to absorb and assimilate a degree of organic materials. To ensure that the marine and freshwater ecosystems are protected, measures are in place to monitor aquaculture activities to minimize environmental impacts:

• Using feed that is easier to digest with less fecal waste from the fish
• Using underwater video cameras to monitor the amount of uneaten feed settling beneath the open pen. Feed levels are adjusted to eliminate uneaten feed resulting in very efficient feed conversion.
• Using electronic devices to control feed.

Feed Conversion Ratios

Feed conversion ratios determine the amount of food required to produce healthy farmed fish. The aquaculture industry strives to keep these conversion ratios as low or efficient as possible. Feeds and feeding methods have become more efficient with more nutrients being used for salmon growth rather than being wasted as fecal matter or uneaten feed.

• An average of 1.5 kg of feed is needed to grow 1 kg of farmed salmon. Many Canadian producers have a conversion ratio of 1:1 or lower.
• In contrast, a cow requires about 7 kg of feed (which includes fish meal) for every 1 kg of weight it gains

Using fish to feed fish

Feeding farmed salmon a diet that includes fishmeal is natural as all salmon in the wild eat a diet of other fish and aquatic animals.

The fish products used in feed pellets for farmed salmon are generally not for human consumption and often include:

• Small fish from other countries that have been fished for fish meal for decades under rigorous regulation to ensure sustainability
• At least 25 per cent of fish meal is from the “trimmings” when processing fish for human consumption. What would have been discarded is now used in fish feed.

Reducing the amount of fish meal and oils in feed

Canadian feed manufacturers are developing new salmon feeds that replace some of the fish-based ingredients with more vegetable and grain protein. Through innovation, Canadian salmon farmers have:

• Reduced their use of wild fish in feed by up to 40 per cent over the last five years
• Produced feed that, on average, includes less than 30 per cent fish meal and oil
• Provided feed which still produces high-quality, nutritious salmon – excellent sources of omega-3 fatty acids for human health

Learn more:

• Fact Sheet: New Fish Feed Goes Green (Freshwater Aquaculture)
• Waste Management