Salmonella species and Campylobacter jejuni cecal colonization model in broilers

Area of Science:

• Veterinary Microbiology
• Food Safety
• Poultry Science

Background:

• Salmonella and Campylobacter are significant poultry-associated pathogens transmissible to humans.
• Effective intervention strategies require reliable models for studying pathogen colonization in mature birds.

Purpose of the Study:

• To establish a reproducible broiler chicken model for Salmonella intestinal colonization in mature birds.
• To evaluate the efficacy of vancomycin treatment in facilitating Salmonella colonization.

Main Methods:

• Chicks were inoculated with Salmonella and Campylobacter at 2 days posthatch.
• Mature broilers (4 weeks old) received vancomycin orally, followed by Salmonella challenge.
• Cecal contents were sampled at 5 and 6 weeks posthatch to quantify bacterial loads.

Main Results:

• Early-life co-infection with Salmonella and Campylobacter led to transient Salmonella colonization.
• Vancomycin treatment in 4-week-old broilers enabled successful Salmonella intestinal colonization.
• Salmonella colonization levels reached 10(6-7) cfu/g at week 5 and 10(2) to 10(4) cfu/g at week 6 post-challenge.

Conclusions:

• A vancomycin-based protocol can establish a mature broiler model for Salmonella intestinal colonization.
• This model is suitable for evaluating live, mature bird interventions against Salmonella.