Quantification of Salmonella Infantis transfer from transport drawer flooring to broiler chickens during holding.

Transportation is a potential point of cross-contamination before broiler chickens arrive at the processing plant for slaughter. Previous studies have associated the use of uncleaned transport containers with the introduction of pathogenic bacteria onto uncontaminated broilers. The objective of this study was to quantify the transfer of Salmonella from transport drawer perforated flooring to broiler chickens during different holding times. For traceability, the flooring of each drawer was inoculated with fecal content slurry containing a marker strain of Salmonella Infantis. Three drawers per treatment were used, and each drawer was subjected to one of the following treatments: pressure wash, disinfectant, and pressure wash (A), pressurized steam followed by forced hot air (B), or no cleaning (C). Drawers were classified as top, middle, or bottom based on their relative position with each other. After treatment, broilers were introduced to each drawer and held for 2, 4, or 6 h. At each timepoint, broilers were removed from drawers, euthanized, and carcasses rinsed to obtain Salmonella counts. Samples under the limit of direct plating detection were enriched, plated, and later confirmed positive or negative. Differences were observed per treatment, holding time, and drawer relative position (P < 0.0001). Broilers placed in transport containers that underwent a cleaning procedure (A or B) had lower levels of Salmonella when compared to broilers placed in noncleaned containers (C). However, most of the samples below the limit of detection were positive after enrichment, indicating that both procedures evaluated need improvement for efficient pathogen inactivation. A decrease in Salmonella transfer was observed after 6 h in rinsates obtained from broilers placed in noncleaned containers (C). Rinsates obtained from top drawers had less Salmonella than the middle or bottom drawers when broilers were placed in transport containers that underwent a cleaning procedure (A and B). The application of pressurized steam and forced hot air was comparable to the use of water washes and disinfectant indicating a potential role in cleaning poultry transport containers.

Application of pressurized steam and forced hot air for cleaning broiler transport container flooring.

In the United States, cleaning poultry transport containers prior to arrival at the broiler grow-out farm is not currently a widely adopted practice in the industry. However, previous studies have shown that transport containers have an important role in cross-contamination before the broilers arrive at the processing plant. The objective of this study was to evaluate the efficacy of pressurized steam followed by forced hot air to clean transport container flooring and compare it to conventional cleaning procedures. Fiberglass and plastic flooring were cut into even pieces and inoculated with chicken intestinal contents containing Salmonella Infantis or Campylobacter jejuni. The cleaning treatments were pressurized steam, forced hot air, pressurized steam followed by forced hot air, water pressure washing, water pressure washing before and after disinfectant, and no cleaning. Counts for Salmonella, Campylobacter, Escherichia coli, coliforms, and aerobic bacteria were assessed. All reductions were made in comparison to noncleaned samples. Forced hot air applied by itself was not efficient in reducing Campylobacter, coliforms, and E. coli; and limited reductions (less than 1 log10 CFU/cm2) were observed for Salmonella and aerobic bacteria. Then, for all bacteria types evaluated, pressurized steam by itself showed reductions of 2.4 to 3.5 log10 CFU/cm2. Samples that were cleaned with a single-pressure water wash showed reductions of 4.0 to 4.6 log10 CFU/cm2 for all bacteria types. For Salmonella, Campylobacter, and E. coli, the greatest reductions were observed when samples were cleaned with pressurized steam followed by forced hot air (4.3-6.1 log10 CFU/cm2) or water washed before and after disinfectant (4.5-6.2 log10 CFU/cm2), and these treatments did not differ from each other. Pressurized steam followed by forced hot air was shown to be an efficient cleaning procedure to reduce poultry-associated pathogens on transport cage flooring, with the benefit of using less water than conventional water cleaning. Processors may be able to adapt this process to reduce potential cross-contamination and lessen the level of pathogens entering the processing plant.

In vitro Effect of Photoactive Compounds Curcumin and Chlorophyllin Against Single Strains of Salmonella and Campylobacter.

Salmonella and Campylobacter are two of the most common foodborne pathogens associated with poultry meat. Regulatory restrictions and consumer concerns have increased the interest for plant-derived antimicrobials and emerging novel technologies. The objective of this study was to determine the antimicrobial activity of photoactive compounds curcumin (CUR) and chlorophyllin (CH) followed by activating light exposure for the reduction of Salmonella and Campylobacter. Peroxyacetic acid (PAA) was also evaluated as a poultry industry standard antimicrobial processing aid. CUR and CH were evaluated in 96-well plates at concentrations of 100, 500, and 1,000 ppm, along with PAA at 100, 200, and 300 ppm, or distilled water (DW). Each well was inoculated with 105 CFU/mL of Salmonella Typhimurium or Campylobacter jejuni, and plates were exposed to activating light (430 nm) for 0 or 5 min. No detectable reductions were observed for Salmonella or Campylobacter when treated with CUR, CH, or 100 ppm PAA. However, when Salmonella was treated with 200 ppm PAA, counts were reduced from 4.57 to 2.52 log10 CFU/mL. When Salmonella was treated with 300 ppm PAA, counts were reduced to below detectable levels (5 CFU/mL). Campylobacter was reduced from 4.67 to 2.82 log10 CFU/mL when treated with 200 ppm PAA. However, no further reductions were observed when Campylobacter was treated with 300 ppm PAA (2.50 log10 CFU/mL). These results indicate that CUR and CH were not effective as antimicrobials under the evaluated conditions, particularly in comparison to the commonly used antimicrobial, PAA.