Antimicrobial resistance of Escherichia coli isolates from spray-chilled sheep carcasses during cooling

Background: Multidrug-resistant bacteria present in food of animal origin raise human and animal health concerns. Objective: To assess antimicrobial resistance of Escherichia coli isolates from sheep carcasses subjected to spray-chilling with water (4 and 10 hours) during cooling. Methods: Thirty surface swabs were collected from carcasses before and after the last water spray in two slaughter periods. In a first assessment (1 st sampling), three spray-chilled carcasses (4 hours), three non-sprayed and one control carcass were sampled. In a second assessment (2 nd sampling), the same number of carcasses and treatments were maintained, but spray-chilling was extended to 10 hours. All samples collected were isolated and submitted to susceptibility test using 16 (1 st sampling) and 17 (2 nd sampling) antimicrobials, respectively. Results: Overall, E. coli isolates were resistant most antimicrobials. Spray-chilled and control carcasses (10 hours) showed resistance to meropenem. Conclusion: E. coli isolates from carcasses subjected to spray-chilling with water for 10 hours had higher antimicrobial resistance to one, two, and four antimicrobial classes, characterizing a multidrug resistance profile. These results highlight the need to monitor health status throughout the meat production processes.