Probiotic Potential of Indigenous (Bacillus sp. RCS1, Pantoea agglomerans RCS2, and Bacillus cereus strain RCS3) Isolated From Cobia Fish (Rachycentron canadum) and Their Antagonistic Effects on the Growth of Pathogenic Vibrio alginolyticus, Vibrio harveyi, Streptococcus iniae, and Streptococcus agalactiae

Large-scale fish farming faces many environmental stresses, which affect their immune systems, growth performance, and physiological homeostasis, resulting in increase susceptibility to infections. Some of the most common bacterial infections cobia ( Rachycentron canadum ) include streptococcosis, vibriosis, furunculosis mycobacteriosis, pastelleurosis. Probiotics could be helpful reducing or limiting incidence severe disease outbreaks. Therefore, present study aimed isolate indigenous species from healthy then selected 3 strains, including Bacillus sp. RCS1 (MW560712), Pantoea agglomerans RCS2 (MW560713), cereus RCS3 (MW560714) gut juvenile’s having advantageous assets positive characteristics. Their analysis indicated presence similar biochemical profiles all effectively utilize carbon sources. The biosafety assessment did not show any pathological symptoms after 10 days injecting with isolated bacteria. results showed that bacteria had low auto-aggregation capacity within first h incubation. strong tolerance when exposed a range pH. Although asymmetrically, slow rise was observed pH 1–8 for RC1, 1–7 RC2, 1–6 RC3. antagonistic effects strains on development pathogens, Vibrio alginolyticus , harveyi Streptococcus iniae agalactiae were investigated using Luria-Bertani (LB) agar plates. All exhibited inhibitory against V. S. . These characterized wide activities, non-hemolytic high survivability heat-treatments safety confidence, antibiotic susceptibility. Generally, characteristics displayed by these they used as potential probiotics aquaculture industry.