Purpose: The objectives of this study were to isolate and characterize endospore-forming bacteria from natural environments as potential probiotics for poultry.
Methods: Sourdough and the gastrointestinal (GI) contents of young broiler chicks were used for the isolation of potential probiotics after preenrichment for endospore forming bacteria. The isolates were screened for their tolerance to acid and bile salt, production of phytase, alpha-amylase, protease, cellulolytic activity, and sporulation capacity. Selected isolates were further identified by 16S rRNA gene sequencing and screened for biofilm formation, compatibility with each other and antagonistic effects against three poultry pathogens including pathogenic Escherichia coli, Salmonella Muenchen, and Enterococcus cecorum.
Results: More than 200 endospore-forming bacteria isolates were recovered from both sources. Based on the screening tests, 47 isolates were selected and identified by 16S rRNA gene sequencing. Six strains were further selected based on their ability to form biofilm and antagonistic effects against poultry pathogenic bacteria. The selected strains were Bacillus amyloliquefaciens and Bacillus subtilis.
Significance: The selected strains demonstrated remarkable potential to be used as probiotic for poultry to improve feed conversion and boost the host resistance to pathogenic bacteria.