Brown seaweed has gained special attention in aquaculture nutrition studies due to its functional bioactive compounds, such as polysaccharides. This study evaluated the functional potential of the brown seaweed, Ascophyllum nodosum , as a natural immunostimulant and growth promoter in Nile tilapia. A 74-day feeding experiment was conducted using 540 fingerlings (initial body weight 18.4 ± 0.2 g), randomly allocated to six diet...