Controlling Salmonella in poultry is an ongoing food safety measure and while significant progress has been made, there is a need to continue to evaluate different strategies that include understanding Salmonella-poultry interaction, Salmonella-microbiota interactions, Salmonella genetics and response to adverse conditions, and preharvest and postharvest parameters that enable persistence. The purpose of this symposium is to discuss different strategies to consider from feed milling to the farm to the processing environment. This Poultry Science Association symposium paper is divided into 5 different sections that covers 1) immunological aspects of Salmonella control, 2) application of Salmonella genetics for targeted control strategies in poultry production, 3) improving poultry feed hygienics: utilizing feed manufacture techniques and equipment to improve feed hygienics, 4) practical on farm interventions for controlling Salmonella-what works and what may not work, and 5) monitoring and mitigating Salmonella in poultry. These topics elucidate the critical need to establish control strategies that will improve poultry gut health and limit conditions that exposes Salmonella to stress causing alterations to virulence and pathogenicity both at preharvest and postharvest poultry production. This information is relevant to the poultry industry's continued efforts to ensure food safety poultry production.
Background: Antimicrobial resistance is rising globally at an alarming rate. While multiple active surveillance programs have been established to monitor the antimicrobial resistance, studies on the environmental link to antimicrobial spread are lacking. Methods: A total of 493 flies were trapped from a dairy unit, a dog kennel, a poultry farm, a beef cattle unit, an urban trash facility and an urban downtown area to isolate Escherichia coli, Klebsiella pneumoniae and Staphylococcus spp. for antimicrobial susceptibility testing and molecular characterization. Results: E. coli, K. pneumoniae and coagulase-negative Staphylococcus were recovered from 43.9%, 15.5% and 66.2% of the houseflies, and 26.0%, 19.2%, 37.0% of the blowflies, respectively. In total, 35.3% of flies were found to harbor antimicrobial-resistant bacteria and 9.0% contained multidrug-resistant isolates. Three Staphylococcus aureus isolates were recovered from blowflies while three extended spectrum beta lactamase (ESBL)-carrying E. coli and one ESBL-carrying K. pneumoniae were isolated from houseflies. Whole genome sequencing identified the antimicrobial resistance genes blaCMY-2 and blaCTXM-1 as ESBLs. Conclusion: Taken together, our data indicate that flies can be used as indicators for environmental contamination of antimicrobial resistance. More extensive studies are warranted to explore the sentinel role of flies for antimicrobial resistance.
Placing 1-d-old chicks on used litter may lead to unexpected health problems due to high bacteriological counts. Composting litter between flocks is one possible method of decreasing bacteriological counts. At the end of two 7-wk broiler growouts, in-house composting of pine shaving litter was performed, and bacterial counts were taken. In the first trial, composted pine shavings attained an internal temperature of 55°C that lasted for 40 h. After the initial temperature gain, the composted litter maintained a steady temperature of 35°C. Aerobic and anaerobic bacterial counts were lower in composted vs. uncomposted litter. Moisture content was lower in the uncomposted pile than the compost pile. Water activity was higher in the composted pile than in the uncomposted litter. Among the 8 treatments in the second trial, litter that was composted, wetted, and covered achieved the highest internal temperatures of >50°C, which was sustained until trial termination (7 d). The other treatments did not achieve a temperature increase of this magnitude and, if not wetted, the observed temperature increase lasted <24 h. In litter that had been composted for 1 wk, moisture content was lower regardless of treatment. Water activity was highest in treatments that had water added and that were not covered. Composted, covered, not wetted pine shavings produced the lowest aerobic and anaerobic bacterial counts. The results of these 2 trials show that in-house composting of pine shaving litter can reduce bacterial counts, especially when the compost pile is covered.