How beneficial bacteria are emerging as powerful alternatives to antibiotics in controlling foodborne pathogens
Picture this: a seemingly healthy chicken thriving in a barn, carrying within its gut a silent threat capable of causing food poisoning in humans. This invisible danger is Campylobacter jejuni, a bacterium that maintains a near-commensal relationship with poultry while posing significant risks to human health 1 .
Growing global concern driving search for alternatives in poultry production.
Beneficial bacteria and consortia revolutionizing poultry health approaches.
Recent studies compare innovative approaches against traditional methods.
Campylobacter jejuni represents one of the most perplexing challenges in poultry production. While it rarely causes illness in chickens, it's a leading cause of foodborne illness in humans worldwide 1 .
Traditional approaches have relied on antimicrobial growth promoters (AGPs) in feed - subtherapeutic doses of antibiotics that not only promote growth but theoretically help control bacterial infections in flocks 1 .
The widespread use of antibiotics in animal agriculture has contributed to a growing global crisis: antimicrobial resistance 2 .
The World Health Organization has classified antibiotic-resistant Campylobacter as a serious threat to public health, prompting intensified research into non-antibiotic approaches 2 .
At the forefront of alternative approaches are probiotics - natural microbes that confer beneficial effects on their host 1 .
While single-strain probiotics offer targeted approaches, another strategy has gained traction: competitive exclusion consortia 1 .
These products contain complex communities of multiple microbial species that work together to create a stable, protective gut environment.
Complex communities stabilized through mutualistic interactions may be more resilient and better at exploiting available resources, leaving little room for pathogens to establish themselves 1 .
Probiotics or competitive exclusion consortia are administered to poultry, introducing beneficial microorganisms to the gut environment.
Beneficial microbes colonize the gut, competing with pathogens for space and nutrients.
Through multiple mechanisms including competition, production of antimicrobial compounds, and immune stimulation, pathogens like Campylobacter are suppressed.
A balanced, diverse microbial community is established, reducing pathogen colonization and improving overall bird health.
Broiler Chickens
Treatment Groups
Days Post-Hatch Challenge
| Treatment Type | Specific Treatment |
|---|---|
| Single-Strain Probiotics | Pediococcus acidilactici (bacterium) |
| Single-Strain Probiotics | Saccharomyces cerevisiae boulardii (yeast) |
| Complex Consortia | Aviguard® (commercial product) |
| Complex Consortia | CEL (experimental consortium) |
| Antibiotic Control | Bacitracin (AGP) |
| Baseline Control | Untreated |
Advanced molecular technique used to analyze microbial communities in cecal samples, identifying which bacteria were present and in what proportions 1 .
| Treatment Group | C. jejuni Burden at Day 30 | C. jejuni Burden at Day 39 | Key Finding |
|---|---|---|---|
| Untreated Control | Baseline | Baseline | Reference for comparison |
| Bacitracin (AGP) | No significant difference from control | Highest burden | Traditional approach less effective |
| Pediococcus acidilactici | No significant difference from control | No significant difference from control | Limited impact on Campylobacter |
| Saccharomyces cerevisiae boulardii | No significant difference from control | Notable decrease (not statistically significant) | Promising but inconclusive |
| Aviguard (Consortium) | No significant difference from control | Significant decrease vs. bacitracin | Superior to antibiotic approach |
| CEL (Consortium) | No significant difference from control | Significant decrease vs. bacitracin | Superior to antibiotic approach |
| Treatment | Key Microbial Shifts | Community Complexity |
|---|---|---|
| Aviguard | ↑ Bacteroidaceae | Less complex |
| CEL | ↑ Rikenellaceae | Similar to other treatments |
| Bacitracin | Distinct from consortia | Increased alpha diversity |
| Research Tool | Function in Study |
|---|---|
| Pediococcus acidilactici | Single-strain probiotic bacterium to test individual microbial effects |
| Saccharomyces cerevisiae boulardii | Single-strain probiotic yeast to evaluate fungal probiotic potential |
| Aviguard® | Commercial competitive exclusion consortium to test complex community approach |
| CEL | Experimental competitive exclusion consortium for novel complex community assessment |
| Bacitracin | Traditional antibiotic growth promoter for comparison baseline |
| 16S rDNA Sequencing | Molecular technique for identifying and quantifying microbial community members |
The complex competitive exclusion consortia (Aviguard and CEL) resulted in significant decreases in C. jejuni burden compared to birds treated with bacitracin, suggesting that replacing dietary bacitracin with competitive exclusion products could potentially reduce Campylobacter burden while also protecting against other pathogens 1 .
The findings from this study represent more than just a comparison of products - they signal a potential paradigm shift in how we approach poultry health and food safety.
The distinct microbial signatures associated with each intervention open exciting possibilities for tailoring interventions to create specific microbial landscapes most resistant to particular pathogens.
While these findings are promising, important questions remain. The varying results between products and farms noted in previous studies highlight the context-dependent nature of probiotic efficacy 1 .
This research illuminates a path forward that works with, rather than against, the microbial world. The traditional warfare approach to pathogens is gradually giving way to a more nuanced understanding of microbial ecology.
The study demonstrates that complex competitive exclusion consortia can significantly reduce Campylobacter burden compared to traditional antibiotic use, offering a viable alternative to indiscriminate antimicrobial use 1 .