Adding an ingredient to feed formulations which contains omega-3s may seem like a simple recipe for success. But it really isn’t that easy, as not all omega-3s are equal. So, picking the right one is crucial and can offer a significant competitive advantage.
Naturally found in algae, plankton and fatty fish like Atlantic salmon and herring, and of course Antarctic krill, it is no secret that omega-3 fatty acids are enormously beneficial for the development and well being of fish’s essential organs, such as the heart, brain, gills and liver. In addition, a mountain of scientific evidence also shows that farmed fish and shrimp, fed omega-3 rich feeds, have an improved tolerance to diseases and stress.
However, while the benefits to aquaculture feed formulations are well documented, what is often overlooked is that not all omega-3s are the same. It is an important point and one which has a significant impact on how quickly and effectively fish and shrimp can benefit from these unique fatty acids.
A water-soluble winner
Omega-3 fatty acids are bound in a chemical structure, as either a triglyceride or a phospholipid. They are very similar but do have slight variations in form and function. For example, triglycerides consist of three fatty acids and glycerol, while phospholipids contain two fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), glycerol and a phosphate linked to a headgroup. This polar headgroup is what makes phospholipids hydrophilic, soluble in both water and fat, which is important for their biological function.
It’s a small difference in composition, but it has an enormous impact on just how quickly and effectively those essential omega-3 fatty acids can be utilized by fish and shrimp.
Proven to be much more effectively absorbed, penetrating into the cell membranes where they can be biologically active, rather than being burned as energy, or stored as fat, omega-3 fatty acids in phospholipid form are a step ahead of their triglyceride cousins.
Indeed omega-3 triglycerides must first be converted to the phospholipid form, before they can be even be taken up by cell membranes.
See short film on phospholipids here:
An essential building-block
Along with being the ideal delivery system for omega-3s, phospholipids are also a natural and integral part of cells. A vital structural component of both cell surface membranes and the internal membranes of cells, helping to maintain their strength, flexibility, and integrity, phospholipids are sometimes referred to as the “life molecule”. As without them, animals would suffer critical cellular dysfunction and as a result drastic health issue.
High omega-3 fatty acids content in cell membranes is associated with fish that can withstand treatment and stress, and omega-3 fatty acids are important for the good functioning of central organs such as the heart, gills and liver. Better health and a lower degree of inflammation may be the reason why we have found a better texture and less fillet splitting with salmon that is fed krill.
A single source
Marine fish and shrimp are unable to produce long chain polyunsaturated fatty acids from the precursors, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) themselves, so they must access these through their diet. In the wild this is achieved through feeding on marine algae and plankton. For aquaculture, this means the addition of a feed ingredient rich in the phospholipid variant of omega-3s. Traditionally a good source has been fish meal and fish oil, but this is a somewhat unstable and unsustainable resource. A practically, economically and nutritionally great alternative is krill.
The carefully managed, truly sustainable resource, Antarctic krill are harvested from the clear waters of the Southern Ocean and are virtually free of environmental contaminants and toxins. Rich in those must-have omega-3 phospholipids, krill also unique in that contains phosphate choline, an important vitamin-like nutrient, vital for nerve signalling, liver and muscle functioning.
Offering a crystal clear phospholipid advantage over rival omega-3 sources, learn more about this truly unique feed ingredient here or sign up to our newsletter below to receive relevant articles.