Bacteriophages as an alternative to the use of antibiotics in poultry breeding

Abstract

Bacterial resistance to antibiotics is an emerging problem worldwide; antimicrobials used in animal husbandry are the most important factor in the propagation of resistance genes, because the amount of antibiotics used in the animal industry is greater than in the medical field. Since phages constitute a safe alternative for the control of human pathogenic bacteria in food, this project aimed to isolate and characterize Salmonella spp. bacteriophages and use them to reduce the presence of this pathogen in poultry at the farm level, without the use of antibiotics. We obtained phage cocktails that showed lytic activity in vitro against 83% of the Salmonella strains isolated from poultry farms. The cocktails with the greatest spectrum of activity against Salmonella were obtained from nearby polluted rivers. We were able to eliminate the pathogen from the chicken intestine when phages were applied 48 hours before the animals were slaughtered, but it is necessary to maintain a permanent monitoring of the phage's lytic activity against resistant strains of Salmonella.