Investigation of Antibacterial Efficiency of Various Lytic Bacteriophages Isolated from Chickens Against Characterized Multidrug-resistant Pathogenic Bacterial Strains

This study targeted isolation and characterization of potential bacteriophages (phages) infecting MDR pathogenic bacteria recovered from chickens and analyzed their efficacy as bio-control agents. A total of 45 different bacterial isolates (18 E. coli, 16 Salmonellae spp., 5 Staphylococcus spp., 2 Pseudomonas spp., 1 Proteus mirbalis, 1 Citrobacter spp., 1 Enterobacter aerogenes and 1 Klebsiella pneumonia) were obtained from chickens in the current study and previous studies. The identified isolates were investigated for the presence of virulence genes and MDR using PCR and disc diffusion method, respectively. Nine purified phages classified morphologically into 3 families (Myoviridae, Siphoviridae and Podoviridae) using Transmission Electron Microscope were recovered from chicken intestinal contents and showed viability at wide pH range, resistance to organic solvents and thermostability at high temperatures (up to 80ºC). The potential phages exhibited various bacterial host ranges using the spot test and the efficiency of plating (EOP) assay. The results revealed the prevalent of pathogenic E. coli and salmonella serovars among the recovered isolates with different virulence and genotypic patterns. The lytic phages were highly stable and have the capacity to infect different pathogenic MDR bacterial strains. This study demonstrated that these promising phages of avian origin could be used to control the pathogenic MDR E. coli and Salmonella serovars which possess public concerns on human health and poultry industry