Chapter 24 - Algae materials: an alternative feed ingredients for the sustainable aquaculture

Abstract

Aquaculture remains one of the fastest-growing food-producing sectors, accounting for almost half of total food fish and substitutes for wild fish. Global fish production was estimated to have reached 214 million tons in 2020, of which, 178 million tons are aquatic animals and 36 tons are algae, largely due to the growth of aquaculture in Asian countries. The global farmed shrimp market continues to grow faster than other aquaculture species. In the aquaculture system, feed is crucial because it provides the necessary nutrients (such as protein, carbohydrate, vitamins, fat, and minerals) for regulating physiological processes, growth, and disease resistance. All equalized feed used in the aquaculture industry has fishmeal as a fundamental component. Nevertheless, a rapidly expanding aquaculture industry uses a crucial protein source. Fishmeal has a number of substitutes that have been identified. Microalgae may have amassed a collection of them due to their affordability, practicality, and nutrient formula, particularly their high protein and amino acid profiles comparable with other dietary proteins. In addition to having a high protein content, microalgae have gained popularity for their abundance in vital fatty acids, vitamins, and minerals, as well as for their antioxidant pigments such as carotenoids. In addition to the high nutritional value, microalgae serve as an effective immune booster in fish and may have the potential for use as an antimicrobial agent in aquafeed. The use of microalgae has been shown to enhance the innate immunity and increase the resistance against pathogenic infection in shrimp. This chapter reveals the suitability of microalgae-derived pellet feed in the sustainable production of fish and shrimp.