Abstract
Pathogenic bacterial namely Streptococcus sp has widely spreads in Seabass culture, particularly in fingerlings. It might caused decreasing production quality and quantity. To improve this problem, a study have been done to feed the seabass by using the combination of immunostimulan and antibiotics. The parameter observed were the survival rate and growth rate. Juveniles of 2 cm in size with Streptococcus symptoms were reared in 6 units of 2 m3 tanks with stocking density of 5,000 fishes per tank. They were fed with artificial feeds mixed by immune stimulant and antibiotics (5gr/kg and 2gr/kg, respectively). The experiment was done with 3 replicates and one control for 20 days. The results showed that the survival rates were significantly different between A and B (control) with 20.2% (3,030 ind) and 12.5% (1,875 ind), respectively. There were no significant different in the growth rates between A and B with body length 5.90 cm and 5.80 cm, respectively.