OBJECTIVES

spp. are one of the leading foodborne pathogens in the world, and chickens are a known reservoir. This is significant considering broiler chicken is the top consumed meat worldwide. In the USA, backyard poultry production is increasing, but little research has been done to investigate prevalence and antimicrobial resistance associated with in these environments.

METHODS

Our study encompasses a farm-to-genome approach to identify and investigate its antimicrobial resistance phenotypically and genotypically. We travelled to 10 backyard and 10 integrated commercial broiler farms to follow a flock throughout production. We sampled at days 10, 31 and 52 for backyard and 10, 24 and 38 for commercial farms. Bird faecal ( = 10) and various environmental samples (soil  = 5, litter/compost  = 5, and feeder and waterer swabs  = 6) were collected at each visit and processed for

RESULTS

Our results show a higher prevalence of in samples from backyard farms (21.9%) compared to commercial (12.2%). Most of our isolates were identified as (70.8%) and the remainder as (29.2%). Antimicrobial susceptibility testing reveals phenotypic resistance to ciprofloxacin (40.2%), an important treatment drug for infection, and tetracycline (46.6%). A higher proportion of resistance was found in isolates and commercial farms. Whole-genome sequencing revealed resistance genes, such as and point mutation, that may confer resistance.

CONCLUSION

Overall, our research emphasizes the need for interventions to curb prevalence of resistant spp. on broiler production systems.