Prevalence and multidrug resistance of species isolated from chickens at slaughterhouses in Nakhon Ratchasima Province, Thailand.

BACKGROUND AND AIM

is a commensal bacteria found in humans and animals, which can cause human nosocomial infections. One of the most contaminated enterococcal sources is poultry meat. Therefore, this study estimated the prevalence and antimicrobial resistance (AMR) profile of from chickens and their meat products at local slaughterhouses in Nakhon Ratchasima Province, Thailand.

MATERIALS AND METHODS

From January 2021 to March 2022, 558 samples from 279 cloacal swabs and breast meat were collected from 31 local slaughterhouses in the area. Then, the samples were screened for using modified de Man, Rogosa, and Sharpe agar. Next, selected Gram-positive, catalase-negative, and cocci-shaped colonies were investigated for enterococcal confirmation using Enterococcosel Agar (EA). We also cultivated the samples directly on EA. However, the disk diffusion method was used to investigate positive resistance profiles to 16 antimicrobial agents. Finally, selected phenotypic multidrug-resistant (MDR) isolates were further assessed to identify AMR genes by polymerase chain reaction.

RESULTS

Investigations showed that the prevalence of isolates from the chicken cloacal swabs and meat samples were 29.75% (83/279) and 28.32% (78/279), respectively. Most positive isolates were resistant to colistin, followed by cefoxitin, cephalexin, and streptomycin. These isolates also showed a prevalence of MDR species (65.22%; 105/161) and 66 patterns. Furthermore, selected MDR (MDRE) from cloacal swabs and breast meat were positive for the resistant extendedspectrum beta-lactamase TEM genes at 71.43% (20/28) and 78.26% (18/23), respectively, whereas other AMR genes detected in the selected MDR enterococci from the cloacal swabs and breast meat were beta-lactamase TEM ( [0%, 1.96%]), Class 1 integrase ( [14.28%, 0%]), colistin ( [3.57%, 0%]), and vancomycin ( [14.28%, 0%]).

CONCLUSION

This study indicated that phenotypic MDRE correlated with extended-spectrum beta-lactamase TEM gene presence, leading to an AMR reservoir that can be transferred to other bacteria.