Synergetic Effects of Synbiotics and Herbs in Diets of Asian Seabass, Lates Calcarifer to Enhance Immunity and Growth

Seabass, Lates calcarifer, has high economic value; hence, it must be cultivated optimally. Constraints in cultivation include pasteurellosis and vibriosis, which disrupt growth and cause mortality. Prevention of pathogenic bacteria can be carried out by boosting fish immunity. Providing natural herbs is one way to increase immune response and prevent infection attacks. Therefore, this study aimed to determine the immune response and growth performance of seabass provided with synbiotics and different herbs (black cumin, turmeric, and bitter) in the feed. The study was conducted at the Lampung Marine Aquaculture and Fishery Center using a completely randomized design with five treatments and four replicates. The treatments were T1 negative (-) control), T2 positive ( +) control), T3 (synbiotics), T4 (herbs), and T5 (mixed). The results indicated that the highest leukocyte number and phagocytosis rate were found in T5 at 5.67 × 10⁶ cells mL⁻¹ and 67.57%, respectively, while the highest phagocytosis index was in T2 at 1.87. The most significant increases in length and weight gain, FCR, and SGR were found in T5 at 12.6 cm, 97 g, 1.62, and 3.86% day⁻¹, while the highest SR at 100% was found in T3 and T5. In conclusion, T5 significantly affected seabass's immune response and growth performance.