This piece, authored by Dr Brett Glencross, was published in the March 2024 edition of International Aquafeed

While marine ingredients have long been the benchmark for feed ingredients in aquafeeds, they are not without their limitations. For starters, there isn’t enough of them. However, when we start to look across the “spectrum” of ingredients that we might consider for using in aquafeeds, we quickly deduce that everything has a limitation of some sort. There is no such thing as the perfect ingredient.

It is in this perspective that a recent review was published [DOI://10.1080/23308249.2024.2315049] that undertook a classic SWOT (strengths-weaknesses-opportunities-threats) analysis of a range of ingredients, including marine, grain and terrestrial animal by-products and a range of novel ingredients as well (e.g., single-cell and insect).  In the review it was noted that the technology readiness of these options varies across and within the different ingredient classes, but importantly it remains important to consider each of the ingredients in terms of the overall options out there.

By comparing the nutritional attributes of each of the various ingredient classes being examined, it became possible to apply an assessment framework based on understanding the critical knowledge required to be able to accommodate any ingredient in the formulation process. Notably, that assessment framework was based on the review “A feed is still only as good as its ingredients”, [DOI: 10.1111/anu.13138] which proposed a series of steps based on; characterisation - palatability - digestibility - utilisation - accessory studies, and critically in that order. Once that framework was laid down, we progressed on comparing all the various ingredients. To do this we used a SWOT analysis, to make some consideration of what future potential may exist across the spectrum and what risks and opportunities each of the various ingredients might bring.

Perhaps the most critical thing we noted was that all ingredients have strengths and weaknesses, and that there is no such thing as the perfect ingredient. However, by better appreciating the positive and negative attributes of each ingredient, it becomes possible to increase the adaptability in being able to respond to the various opportunities and their use in feeds. Another feature discussed was complementarity and the capacity of ingredients to work in synergy with other ingredients. As suggested, there may not be such a thing as the perfect ingredient, but maybe by harnessing the strengths of individual ingredients we have a better chance of making the perfect feed.