| dc.description.abstract | Intensive culture activity of tilapia can be affected by bacterial illness attack like streptococcosis, so in this research it was used probiotic bacteria into tilapia feed to overcome it. There were 5 feed treatment that were NB21b probiotic 1% (v/w), L1k probiotic 1% (v/w) and NB21b probiotic 0.5% (v/w) + L1k probiotic 0.5% (v/w), positive control, and negative control. Here tilapia has average weight 24.9±2.20 g/fish and was gived treatment feed during 21 days before challenge test. After that, the fish was challenged by cohabitation, where cohabitation fish was injected Streptococcus agalactiae with density 104 CFU/ml. The results showed that L1k 1% (v/w) probiotic bacteria can increase survival rate and immune system especially in phagocytosis activity, which prevented the infection of Streptococcus agalactiae effectively. | en |
