Isolation and Effect of Antagonistic Bacteria against Vibrio in Shrimp Aquaculture

A total of 22 strains were isolated from aquatic environment.The potential probiotic strains were selected by dot inoculating method to screen the bacteria with antagonism property.The isolate A4 was identified as Bacillus subtilis based on conventional biochemical tests and 16 SrRNA sequence homology,which exhibited significantly inhibitory activity against Vibrio parahaemolyticus,Vibrio alginolyticus and Vibrio brilliant.The probiotic effect of Bacillus subtilis showed that it could reduce the levels of the pathogenic bacteria and affect shrimp health after two days of culture(P0.05).The Bacillus subtilis had potential applications for controlling pathogenic bacteria,which could be used as biocontrol agents in the aquaculture industry.