Bacteriophages in Poultry Practice: A Precision Tool for Salmonella Control and Antimicrobial Resistance Management

Bacteriophages (phages) are the most abundant organisms on Earth and are widely recognized as viruses of bacteria and archaea. Their global population is estimated at approximately 10³¹, nearly ten times higher than bacterial numbers. Structurally, phages consist of nucleic acids enclosed within a protein capsid, with most carrying double-stranded DNA genomes. This extreme abundance and host specificity make them highly relevant in veterinary medicine, particularly in poultry systems facing increasing antimicrobial resistance (AMR)¹. 

Why Phages Are Important in Poultry Systems 

In modern poultry production, maintaining gut health and controlling bacterial infections is a key challenge. Unlike antibiotics, bacteriophages act with high specificity toward target bacteria, preserving beneficial gut microbiota and reducing the risk of dysbiosis and secondary infections. 

From a field veterinary perspective, phages offer¹: 

• High bacterial specificity with minimal disruption of microbiota  

• Cost-effective isolation and production compared to antibiotics  

• Self-amplification at the site of infection  

• Biofilm disruption capability  

• Activity against multidrug-resistant (MDR) pathogens  

These properties position phages as promising precision tools in poultry disease management. 

Phage Applications in Salmonella Control 

In poultry production, phage therapy is increasingly explored for controlling Salmonella, a major zoonotic pathogen responsible for foodborne infections worldwide. Phage-based interventions help reduce bacterial load in birds as well as contamination of poultry products. 

Common field applications include: 

• Oral administration via drinking water or feed  

• Aerosol sprays in hatcheries  

• Egg surface decontamination  

• Direct application on contaminated products  

These approaches are effective in reducing both horizontal and vertical transmission of Salmonella in poultry systems^1,2. 

Studies have shown that phage cocktails can significantly reduce intestinal colonization and environmental shedding, improving flock health and food safety outcomes. 

Limitations in Field Application 

Despite strong potential, several challenges limit routine field adoption: 

• Narrow host range requiring precise phage selection  

• Emergence of phage-resistant bacterial strains  

• Environmental instability affecting phage survival  

• Lack of standardized commercial formulations  

• Regulatory barriers for veterinary use  

These factors currently restrict widespread industrial-scale implementation.  

References 

1. Khan MA, Rahman SR. Use of phages to treat antimicrobial-resistant Salmonella infections in poultry. Veterinary Sciences. 2022 Aug 18;9(8):438. https://www.mdpi.com/2306-7381/9/8/438 

2. Wernicki A, Nowaczek A, Urban-Chmiel R. Bacteriophage therapy to combat bacterial infections in poultry. Virology journal. 2017 Sep 16;14(1):179. https://link.springer.com/content/pdf/10.1186/s12985-017-0849-7.pdf