Isolation, Characterization and Evaluation of Lytic Activity of Bacteriophages from Poultry Droppings against Selected Bacterial Pathogens

The global rise in antimicrobial resistance (AMR), particularly among poultry-associated pathogens such as Escherichia coli and Staphylococcus aureus, necessitates alternative strategies beyond conventional antibiotics. This study aimed to isolate, characterize, and evaluate the lytic potential of phages derived from poultry droppings against selected bacterial pathogens. Phages were isolated using enrichment, filtration, and plaque assay techniques, followed by transmission electron microscopy (TEM), host range determination and stability assessments across varying temperature and pH conditions. The isolated phages exhibited strong lytic activity against S. aureus and E. coli with high titers ranging from 1.2 × 10³ to 3 × 10⁴ PFU/mL. TEM analysis revealed icosahedral phage structures; E. coli phages were 20–30 nm, suggestive of the Microviridae family, while S. aureus phages were 50–80 nm, likely belonging to the Podoviridae or Tectiviridae families. Optimal lytic activity was recorded at 37°C and pH 7.0, and adsorption efficiency was enhanced in the presence of MgCl₂. These findings suggest that poultry faeces harbor bacteriophages with promising biocontrol potential against antibiotic-resistant pathogens, supporting their application in phage therapy and sustainable poultry farming.