Plant-derived feed ingredients in aquaculture: A comprehensive review of their effects on fish growth performance and nutritional outcomes

The dynamics of the fisheries and aquaculture industry have evolved rapidly in recent decades, with a marked increase in production capacity, trade, business, and consumption, which has led to additional pressure on aquaculture feed resources. Despite fishmeal being a vital source of high- quality protein in farmed fish, its application in fish feed has been challenged on several fronts, including its scarcity, shortage, and environmental degradation. Plant-based protein ingredients are considered potentially useful alternatives to animal-based protein sources because they are readily available, less expensive, and less reliant on aquatic resources. This review critically summarizes the existing literature on the use of plant-based proteins in fish feed and their processing to enhance their suitability. Major sources of plant-based proteins, including soybean meal, pea protein, rapeseed meal, and corn gluten, are discussed in terms of their protein content, amino acid composition, and the presence of anti-nutritional factors (ANFs), which can limit the digestion and absorption of other nutrients. This review also suggests that the application of advanced processing technologies, including fermentation, heat processing, enzyme addition, and extrusion, can be utilized to reduce ANFs and improve the bioavailability of nutrients. The economic and environmental impact of utilizing plant proteins is also explained in the context of reducing feed costs and making fish farming more sustainable. Finally, the research areas for the future were determined, including the development of feeds, the adoption of new processing methods, and the combination of plant proteins with other sustainable foods to meet the increased global demand. This synthesis provides valuable insights for feed manufacturers, aquaculture producers, and researchers interested in adequate sustainability and efficiency of aquaculture by innovative plant-based feeding strategies.