Screening and identification of Bacteriophage that is effective against Avian Pathogenic E. coli- a potential tool for controlling Antibiotic Resistant Colibacillosis

Antimicrobial resistance (AMR) in Escherichia coli is an escalating concern in the poultry industry, driven largely by the widespread and often improper use of antibiotics for disease treatment and growth promotion. E. coli, a common commensal bacterium of the gastrointestinal tract, includes avian pathogenic strains (APEC) that cause colibacillosis, leading to high morbidity, mortality, reduced productivity, and significant economic losses in poultry. The increasing prevalence of multidrug-resistant E. coli has compromised the effectiveness of conventional antibiotics, a problem compounded by high antimicrobial consumption globally and in Nepal, where Watch group antibiotics dominate both clinical and poultry use. In the absence of significant progress in developing new antimicrobials, bacteriophages have re-emerged as a promising alternative due to their ability to specifically target and kill bacteria. Although phage therapy faces challenges such as narrow host range, lysogenicity, immune responses, and the need for strain-specific isolation, advances in classical microbiology and genomic characterization offer opportunities to rapidly identify pathogens and develop tailored phage-based interventions to control colibacillosis and reduce the burden of AMR in poultry.