Water Quality Shapes Microbial Communities in Poultry Drinking Lines

The Problem

Biofilms form naturally inside poultry drinking water lines, creating an environment where bacteria can persist and multiply. While farms routinely test water sources for microbial safety, little attention has been given to the biofilms coating the inside of water lines. Elevated levels of sulfur and iron in well water, common in rural poultry operations, may support the survival of harmful bacteria. However, it is unclear how water quality history shapes the microbial composition of these biofilms or their potential role in Salmonella persistence.

The Work

Tomi Obe, an Assistant Professor with the Departments of Poultry Science and Food Science and a researcher with the Arkansas Agricultural Experiment Station, and lead author Tolulope Ogundipe, DVM, compared biofilms and litter samples from 10 commercial broiler houses. Five had historically normal sulfur-iron water, and five had historically high sulfur-iron water. The researchers analyzed the microbial communities present in both the litter and the water line biofilms to identify differences in bacterial composition and potential correlations with the presence of Salmonella.

The Results

The researchers found no major differences in Salmonella quantity between farms with high versus normal sulfur-iron water. However, normal sulfur-iron water farms showed a higher prevalence of Bacillus species with probiotic traits. High sulfur-iron water farms exhibited more pathogenic Bacillus species in biofilms. The researchers noted that one farm with low Salmonella levels in its biofilm had high Salmonella counts in its litter, and vice versa for another. These results suggest that biofilm composition and litter contamination may not always align. While good water quality doesn’t eliminate biofilms, it does shape their microbial makeup.

The Value

Understanding how water quality history affects biofilm composition provides new insight into pre-harvest Salmonella control strategies. The research highlights the importance of routine monitoring of poultry water lines, not just the water source. In the future, adapting technologies like “sight glasses” to visually inspect pipelines could offer practical tools for farmers to detect biofilm buildup and microbial content.