Salmon eat more feed when served krill
Krill is found in all the world’s oceans, making it a natural food choice for fish. This tiny crustacean is perfectly composed of important nutrients, like proteins, fats and vitamins ensuring that the fish are properly nourished so that they grow to be healthy and more resilient. In addition, krill has a natural special effect: it contains several substances that attract salmon and makes them want to eat more. Various attractants, such as nucleotides, water-soluble amino acids, and the substance TMAO, all affect receptors in the mouths and noses of salmon and stimulate their need to feed.
Krill is an important part of the diet of wild salmon in the oceans, so it is not a surprise that it is a good raw material also for farmed salmon. When krill is part of the fish feed, even at low levels of inclusion, the feed tastes better and will increase the fish appetite and feed intake. This makes krill is a good option in feeds with raw materials that lack appealing flavor.
Salmon thrive with krill in the feed
When fish eat more, they benefit from a richer supply of the nutrients that stimulate growth and maintain health. Krill may be best known as a good source of omega-3, but krill meal also contains the amino acids that fish need to build muscle and other tissues, as well as vitamins and minerals that supports cell function and protect tissue from damage. The entire package of nutrients from krill, including several important vitamins, astaxanthin and minerals contribute to the improvement of several health parameters observed when fish has been fed with krill.
Phospholipids and omega-3 are essential parts of a healthy diet for salmon. A sufficient amount of omega-3 is necessary to keep the cells healthy, and high amounts of omega-3 in the feed is associated with improved fish welfare during stressful situations, such as disease, sea lice treatment, and other types of handling. Omega-3 fatty acids are particularly important for maintaining well-functioning central organs, including the heart, gills, liver, and skin.
When omega-3 is delivered in the form of phospholipids, this affects the uptake and distribution of fatty acids in the fish. A greater amount of those valuable omega-3 fatty acids will reach important organs and contribute to healthier cells when in phospholipid form. This, in turn, helps the fish withstand stress. The phospholipids in krill are also carriers of choline. Choline is a vitamin-like substance that has recently been shown to be essential for the absorption of fatty acids, including omega-3 from the gut, and it’s important for vision and normal cell production in animals.
Improving salmon welfare
In the fish farming industry, fish welfare is key to producing salmon in both a humane but also economically sound way. Including krill in the feed will contribute to improved fish welfare in the following ways:
- The fish maintains its appetite even in stressful situations because the feed has an appealing flavor. The fish therefore have richer access to the nutrients, and the effect is further enhanced by the support krill has on the intestinal uptake of the nutrients.
- The fish has access to important nutrients, including vitamins and minerals, which improve its immune system and help them resist infections and other developmental damage.
- The fish will become more robust and better able to cope with stressful conditions such as delousing, transfer or other unforeseen scenarios that cause stress.
When you add krill to the feed, production improves along several parameters. The farming facilities experience increased feed intake, enhanced growth, and better health. This leads to a shorter production time and in the slaughterhouses they will also experience better fillet yield and quality. A recently published study that reviewed the findings from 18 previously released studies since 1988, showed that fish eat better and grow more, while fillet quality improves and overall health is better, when krill meal is included in the diet.
Read more about this study here.