Phosphorus in Salmonid Aquaculture: Sources, Requirements, and System-Level Implications

This review provides a comprehensive synthesis of phosphorus (P) dynamics relevant to salmonid aquaculture, with a particular focus on Atlantic salmon. It explores the global P cycle, the chemical forms of P in aquatic systems, and the implications of P sourcing, processing, and availability in aquafeeds. The review distinguishes between digestibility and availability of P, summarizes requirement studies, and evaluates the contribution of marine, animal, vegetable, and inorganic sources to dietary P. It also examines how aquaculture system design, particularly recirculating aquaculture systems (RASs), influences P accumulation and emissions. By integrating nutritional, physiological, and environmental perspectives, this review offers a uniquely holistic view of P efficiency and sustainability in salmonid aquaculture.