Applications of Nutraceuticals in Aquaculture: Improvement in Growth, Immunity and Disease Management

Nutraceuticals are promising functional feed additives in aquaculture, providing natural approaches to improve growth, feed utilization, immunity, stress tolerance, and disease management. Derived from terrestrial and marine sources, they include amino acids, fatty acids, nucleotides, vitamins, minerals, polysaccharides, herbal extracts, probiotics, prebiotics, organic acids, and exogenous enzymes. Their use is increasing as sustainable alternatives to antibiotics and therapeutic chemicals, whose excessive application can contribute to antimicrobial resistance and environmental residues. Nutraceuticals enhance performance through antioxidant defense, non-specific immunity, gut microbiota modulation, improved nutrient digestibility, and stress reduction. Immunostimulants such as β-glucans and chitin enhance disease resistance, while probiotics, prebiotics, and synbiotics promote intestinal health. Exogenous enzymes improve plant-feed digestibility, and dietary administration offers a practical delivery method, although nanodelivery may enhance targeted delivery. Despite their potential, further research is needed on species-specific doses, synergistic interactions, mechanisms, delivery, and regulation. Overall, nutraceuticals support healthier, productive, and sustainable aquaculture