The evolution of nutritional innovation in aquafeeds 

Almost 30 years of research have changed how we understand nutrition in aquaculture. Today, we know much more about what fish and shrimp need, what they can utilise and what happens to nutrients once they are absorbed.  

Protein. Fat. Energy. For many years, these were some of the main numbers used to define an aquafeed. They are still important, of course, but they only tell part of the nutritional story. 

This flexibility depends on knowing much more about the nutrients and raw materials themselves. 

Take protein, for example. Fish do not really have a requirement for crude protein as a number. They require amino acids in the right quantities and balance. If an essential amino acid is limiting, adding more protein will not necessarily give you better performance. 

Energy works in a very similar way. It is not just how much energy is in the feed, but how much is available to the fish. Protein, lipid, and starch sources can all influence energy digestibility.  

This knowledge gave nutritionists more room to formulate. Different raw materials and different levels of protein and energy could be used to reach the same performance, as long as the nutritional requirements of the fish were met. 

And the knowledge kept growing. 

Today, there is much more behind a feed formulation than the numbers you see on a specification. 

We can look at what is digestible, what is available and how nutrients work together. We can account for differences between species, life stages and production conditions. And increasingly, we can look beyond digestion to what the animal actually does with these nutrients. 

Because digestible does not necessarily mean retained. 

Once absorbed, amino acids help build the proteins needed for growth and tissue development. However, if they are not used for protein synthesis, they can be broken down and used as an energy source or converted into body fat for storage. 

That is an important distinction. If the aim is better performance, the answer is not necessarily to put more protein or more energy into the feed. There is also an opportunity to use the nutrients and energy already there more effectively. 

Almost 30 years on, formulation looks very different. The focus has moved from what goes into the feed, to what is available to the animal, and now increasingly to what the animal retains. The science has become more sophisticated, and the tools have evolved with it. But our formulation philosophy is still the same: to understand nutrition better, so every kilo of feed can do more.