Antarctic Krill - a Sustainable Protein Source for Fish and Shrimp

Written by Lena Burri, Director R&D, Animal Nutrition and Health

Krill is an important source of protein, omega-3 fatty acids and feed attractants which makes it a great ingredient in feeds for fish and shrimp.

Facts on krill

Krill is a shrimp-like swarming pelagic crustacean, which is used as a feed ingredient in diet formulations, mainly in the form of a high-protein krill meal.
Krill is a feed attractant and shrimp and fish growth accelerator.
Krill is a sustainable and pure alternative to fish meal and is characterized by a high content of omega-3 phospholipids.
In shrimp farming, krill is given to improve yield and stress resistance without increasing production costs.
In fish farming, krill not only increases yield, but also improves fillet quality and overall fish health.

Krill - a sustainable source

Krill is one of the most abundant species on earth with a biomass of around 500 million tons. The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) restricts harvesting to a specific region in the Southern Ocean, Area 48, and to an annual krill harvest of 1% of the total biomass (the precautionary level for other fisheries is 10% of the total biomass). Aker BioMarine’s krill fishery has been certified by the Marine Stewardship Council (MSC) as being sustainable and 100% traceable.

Krill benefits and use

Due to its inherent advantages – i.e., feeding stimulants, omega-3 fatty acids bound to phospholipids, highly digestible peptides, naturally pure and stable, sourced sustainably – krill inclusion into shrimp and fish feed improves growth and yield. In particular, in diets low in fish meal, krill’s feed attractants increase palatability and improve growth performance. Moreover, krill is used in functional feeds for fish to increase fillet quality. Interestingly, reduced mortality and heart pathology during viral infection is seen in studies with salmon fed krill meal.

A continued sustainable growth of fish and shrimp farming

Continued growth of aquaculture and the change from small-scale to high intensity, industrial farming has increased the need for sustainable protein sources in both shrimp and fish feeds. However, fish meal supplies from wild-caught fish have stagnated.

A way to address the high demand and fish meal shortage is to replace fish meal with soybean meal, which increases cost effectiveness and sustainability of commercial feed. However, soybean meal has a different organoleptic profile than fish meal. Reduced palatability, as well as anti-nutritional factors causing low digestibility, can lead to impaired growth performance of shrimp and fish. Moreover, fish meal is of significant dietary value as a source of nutrients, including minerals and omega-3 long-chain fatty acids that are absent in soybean meal. In contrast to marine lecithins that contain omega-3 fatty acids in phospholipid form, soy lecithins are particularly rich in the pro-inflammatory omega-6 fatty acid, linoleic acid.

Which nutrients does krill contain?

Approx. 60% protein with nutritionally well-balanced amino acids
25% lipids that are characterized by a high amount of phospholipids (around 40%)
Omega-3 fatty acids (EPA and DHA)
Astaxanthin esters

The antioxidant astaxanthin provides pigmentation and is known to have anti-inflammatory properties by the ability to scavenge free radicals, thereby counteracting oxidative stress and damage to proteins, lipids and DNA.

Moreover, krill meal is rich in chitin from the exoskeleton and soluble compounds like trimethylamine oxide (TMAO), free amino acids and nucleotides that may all act as feeding stimulants. Feeding stimulation by partial replacement of fish meal by krill meal in diets leads to increased growth of shrimp and fish, also seen to be true in situations of feeding depression (e.g. high vegetable diets) or stress conditions (e.g. change in salinity or temperature for shrimp and seawater transfer for salmon).

Want to learn more? Have a look at our products or download our booklet on the benefits of krill for fish farming below.

Krill meal supports better aquaculture outcomes during challenging winter season

In many salmon producing countries, winter is a time of cold-water temperatures and stormy weather. These conditions may cause stress and challenge fish welfare, as salmon becomes more vulnerable due to the reduced state of its immune system under cold temperatures. Ensuring that the feed is attractive and that important nutrients are easily accessible to the fish may support the salmon in withstanding these challenging conditions. A robust fish is better equipped to avoid disease and will more quickly recover following any sickness or stressful events.

QRILL Aqua at Aqua Nor 2023: Unveiling krill’s role in fish nutrition

The aquaculture event of the year, Aqua Nor, is right around the corner, on 22-24 August in Trondheim, Norway. With participants from around the globe, Aqua Nor is where leaders and experts from across the industry gather to discuss the future of fish farming.

Krill meal: a powerful and reliable ally for aquafeed formulations

One of aquaculture’s major concerns is to deliver high-quality products for human consumption. The diet given to farmed fish and shrimp must contain all the essential nutrients to deliver healthy animal products to consumers. However, the current aquaculture industry is facing a challenging quest: reducing and even removing fish-based products from aquafeeds while keeping nutritional quality and feed performance. Shifting from fish meal-based diets to plant-based or alternative protein and lipid sources has proven to be an arduous task. The solution can rely on krill meal, a powerful supplement produced from Antarctic krill. But why is krill so appealing for aquafeeds? The secret of krill meal is its unique blend of proteins, lipids, antioxidants, vitamins, and minerals. This makes it an ideal feed additive to fill the nutritional gaps of more sustainable plant-based or alternative animal diets.