Farmed #salmon are primarily fed a diet of fishmeal and fish oils, which provide essential nutrients for their growth and development (source: WWF). Fishmeal is derived from small fish like sardines, herring, and anchovies, processed to remove oil and ash, and is rich in proteins, fats, and vitamins important for salmon. Fish oils, on the other hand, supply essential fatty acids such as omega-3, crucial for cardiovascular health and the nervous system of salmon.
While farmers may also use alternative protein sources like soybean meal and maize meal, these are generally considered less ideal for salmon nutrition (source: The Guardian). It's worth noting that the use of these feeds can have negative environmental impacts, as overfishing of the small fish used for feed production can contribute to the depletion of fish stocks.
Dyes are employed in salmon farming to enhance the color of their meat and make it more appealing to consumers. The commonly used dyes in salmon farming, such as canthaxanthin and astaxanthin, are natural pigments derived from algae (source: Aquaculture Stewardship Council). These dyes are added to salmon diets to intensify the natural pink hue of their flesh.
Criticism has been directed towards the use of dyes in salmon farming due to potential health concerns for both the fish and consumers. Dyes may also be used to mask the quality of farmed salmon, as their diet and environment can result in paler flesh compared to wild salmon. Furthermore, an inadequate diet with vegetable protein or imbalanced use of dyes and additives can lead to health issues and mortality among salmon, affecting both farm productivity and product quality (source: Salmon & Trout Conservation).
Dysentery can be a challenge for salmon farms, particularly when hygienic conditions are insufficient. Bacteria from the Aeromonas genus, especially Aeromonas salmonicida, can cause dysentery in salmon, leading to significant mortality among juvenile fish. Once it spreads in a fish population, controlling the disease becomes challenging (source: Food and Agriculture Organization).
It is important to note that fish producers using sustainable production methods often opt not to use dyes and promote the consumption of sustainably caught wild fish (source: Marine Stewardship Council).
The use of insect protein as feed for salmon is an emerging practice in aquaculture. Insects and their larvae are protein-rich and can be grown sustainably, making them a suitable and palatable alternative to traditional ingredients like fish or soy. Incorporating insect protein into their diet reduces mortality and helps prevent various diseases that may arise when salmon are fed vegetable protein (source: Aquaculture).