Feed for farmed fish must incorporate important levels (35-50%) of highly digestible proteins and high energy through high quality fats, to maintain their activity and growth. Feed also depends on the growth stage of the animal.
The raw materials available for the manufacturing of such aquafeed currently come from three main origins:
(i) Vegetable by-products from wheat, soya, and maize.
(ii) Fish meal and oil from fish and marine crustaceans although their share in feed is decreasing.
(iii) In some cases, also by-products from the processing sectors and the terrestrial animal production sector, which are highly nutritious.
Nowadays, more sustainable feeding systems are being promoted, limiting the dependence on fishmeal and fish oil from wild stocks for food production, for example, and encouraging the use of alternative protein ingredients, such as algae or insects, or waste from other industries. This is also reflected in the Strategic guidelines for a more sustainable and competitive EU aquaculture for the period 2021 to 2030. It is worth mentioning that the use of fishmeal and fish oil from wild stocks over time has decreased in several carnivorous species (e.g. salmon).