Latife Ceyda Irkin
The rapid expansion of aquaculture has increased the need for sustainable nutritional strategies that support fish growth, health, welfare, and resilience to environmental and infectious stressors. In this context, algae and algae-derived bioactive compounds have attracted considerable attention because of their diverse nutritional and functional properties. Microalgae and macroalgae provide proteins, omega-3 polyunsaturated fatty acids, carotenoids, polysaccharides, polyphenols, vitamins, minerals, peptides, and other bioactive compounds that may influence antioxidant defense, immune responses, intestinal function, gut microbiota, stress tolerance, and disease resistance. Recent studies indicate that dietary algae can improve growth performance, feed utilization, physiological condition, and resistance to stress and disease in several cultured fish species. However, their effects depend on algal species and strain, chemical composition, processing, fish species, inclusion level, feeding duration, and environmental conditions. This review summarizes current knowledge on algae and algae-derived bioactive compounds in aquaculture, with particular emphasis on fish nutrition, health, welfare, intestinal function, antioxidant defense, stress tolerance, and disease resistance. The potential and limitations of major compounds, including fucoidan, laminarin, astaxanthin, omega-3 fatty acids, phycobiliproteins, polyphenols, and bioactive peptides, are also discussed. Overall, algae represent multifunctional and promising resources for developing sustainable nutritional strategies and improving fish health and resilience in modern aquaculture.
Microalgae, Macroalgae, Nutrition, Disease, Antioxidant Defense.