Authors: ABDELKARIM MAHDHI, FATHI KAMOUN, AMINA BAKHROUF
Abstract: To evaluate the potential probiotic effect of B. coagulans and B. subtilis strains toward Artemia cultured in different gnotobiotic conditions, antibacterial and adherence assays were investigated and challenge tests with Artemia larvae were performed. Virulent V. alginolyticus (IFL), isolated from infected fish, was tested for comparative purposes. The bacterial strains B. coagulans and B. subtilis produced antimicrobial activity against the pathogenic Vibrio species, including V. alginolyticus isolated from infected fish, and inhibitory zones that ranged from 12 to 20 mm in diameter. An adherence assay revealed that these potential probiotic bacteria are fairly adherent, with a values ranging from 0.10 to 0.32 at 595 nm. Challenge tests with Artemia larvae demonstrated that B. coagulans and B. subtilis have no impact on survival, but do enhance growth and protection against the pathogenic Vibrio. On the basis of these results, it is suggested that the tested Bacillus strains in this study show tremendous potential for use as a probiotic in Artemia cultures, particularly with regard to improving the survival and growth of Artemia larvae and their ability to inhibit the pathogen in in vivo and in vitro conditions.
Keywords: Artemia, probiotics, Bacillus, pathogenic control, adhesion
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