Abstract
Two semi-purified experimental diets with and without enzymatic supernatant of Porphyra (ES; 0 and 3% inclusion levels) were formulated using white fish meal as the primary protein source. Juvenile black sea bream (average initial body weight 1.3±0.1 g, 20 fish per tank) were distributed in two treatments with three replicates and maintained in a thermo-controlled filtered sea water (32-34 psu, 25°C) aquaria (100 l) under an 12L:12D photoperiod. Fish were hand fed three times a day at 09:00, 13:00 and 17:00 at 3% body weight on each diet in dry basis.
Weight gain and specific growth rate were found almost same between the two dietary groups while ES addition significantly (P⟨0.05) improved survival, nutrient utilizations and retentions. Both groups exhibited similar levels of body nutritional profile in terms of proximate and fatty acid compositions except for crude lipid level in dorsal muscles which was significantly higher (P⟨0.05) in group with ES. The results demonstrated the ability of ES to improve the growth performance, survival and biochemical composition of black sea bream.
