Impacts of on-farm water sanitation practices on microbial hygiene in poultry waterlines and efficacy of sodium hypochlorite-based product on foodborne pathogens

The microbial water quality of poultry water supplies can be correlated to bird health, livability, overall performance, and human food safety. On-farm microbial evaluations were conducted to understand microbial hygiene of poultry waterlines based on water sanitation practices. With on-farm study I, 2 farms were selected: Farm A and Farm B; that did not practice water sanitation consistently during the flock grow-out period. Prevalence tests for specific pathogens- Salmonella, E coli, Campylobacter, Listeria, and Staphylococcus were performed for both farms by collecting swab samples post bird harvest from waterlines and plating in specific growth media. With the on-farm study II, 1 broiler farm with 4 barn units that treated water (Chlorine [Cl]= ∼ 1 ppm) during the flock grow-out period and flushed waterlines between flocks using concentrated chlorine solution (>1,000 ppm) was selected. Swab samples (1 from each barn, n = 4; each sampling occasion) were collected on 3 occasions-before flushing, after flushing, and at the end of the grow-out period (d 42) to understand biofilm growth nature in poultry waterlines. Additionally, a separate in-vitro study was conducted to understand the efficacy of a commonly used poultry drinking water sanitizer product (sodium hypochlorite, 8.25%) against specific foodborne pathogens: Salmonella Enteritidis (SE), E. coli and Listeria. Results from the on-farm study I showed that Farm A and Farm B were positive for Listeria and Staphylococcus, whereas these farms were found negative for other species tested. The findings from on-farm study II showed that biofilm reestablished (>4 log₁₀ cfu/mL) in waterlines by the end of grow-out cycle despite waterline cleaning and consistent water sanitation during flock grow-out period. The in-vitro test showed that the efficacy of chlorine-based water sanitizer at the field application dose rates was affected by pathogen load in water and pathogen types. The overall results from on-farm or in-vitro studies indicated that poultry growers need to emphasize consistent and robust poultry drinking water sanitation practice in their farms to keep the acceptable bacterial levels in poultry water supplies or water systems.