Antibacterial Activity of Probiotic Bacteria Isolated From Broiler Feces and Commercial Strains

The extensive use of antibiotics in animal farms to promote the growth rate and prevent the enteric pathogen has led to the development of antibiotic-resistant bacteria and drug residues in the birds body. in the recent years, probiotics have been constantly studied for their inhibitory effects on pathogenic bacteria. the current study aimed to assess the effect of magnesium oxide on controlling serum phosphorus levels and evaluate its side effects. antibacterial activity of local and commercial probiotic bacteria was investigated using colony overlay assay. then antibacterial activity of local and commercial probiotics against each pathogen, salmonella typhimurium , escherichia coli and staphylococcus aurous were compared. local strain of lactic acid bacteria had significantly higher antibacterial activity compared to those of the commercial probiotics. local probiotics showed a significantly stronger activity against staphylococcus aureus , salmonella typhimurium and escherichia coli compared to all commercial probiotics. administration of mono strain of lactobacillus salivarius es1, or co-administration of es1 and l. salivarius es6, is not only more effective than commercial probiotics against salmonella spp., staphylococcus spp. and e.coli , but also, will have no negative effects on micro flora balance of local birds.