Effects of alga Sargassum angustifolium extract on growth performance, survival rate and body composition of the Asian sea bass ( Lates calcarifer)

The aim of this study was to evaluate the effect of macroalga Sargassum angustifolium extract on growth performance, survival and carcass composition of Asian sea bass, Lates calcarifer. For this purpose, 144 pieces of fish with an average weight of 37g were completely randomized with 4 treatments and 3 replications for 56 days, and were fed diets containing 0 (control), 100, 200 and 400mg of alga extract per kg of food. The results of this study showed that the use of alga extract at the rate of 200mg/kg could improve growth and nutrition performance (P<0.05), but the higher concentration of this alga in the diet had opposite effect. The results of carcass biochemical composition analysis also showed that changing the concentration of algae extract in the diet of fish did not have a significant effect on moisture, lipid and protein of this fish (P<0.05). Therefore, the extract of this alga at a concentration of 200mg/kg can be considered as a supplement to growth and nutrition in the diet of Asian sea bass