Zhongguo shipin weisheng zazhi (Mar 2022)

Prevalence and antimicrobial susceptibility of Escherichia coli in raw chicken and pork from Beijing

  • WU Xuan,
  • YANG Lu,
  • LIU Yanchao,
  • WU Yige,
  • LI Hui,
  • SHAO Bing

DOI
https://doi.org/10.13590/j.cjfh.2022.02.004
Journal volume & issue
Vol. 34, no. 2
pp. 211 – 216

Abstract

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ObjectiveTo investigate the contamination characteristic， antibiotic resistance phenotype and genotype of Escherichia coli （E.coli） in raw chicken and raw pork in Beijing.MethodsA total of 259 meat samples （91 pork and 168 chicken） were randomly collected from large and small supermarkets and farmer’s markets in various regions of Beijing. E.coli was isolated after enrichment. The isolated strains were identified by MALDI­TOF/MS and 16 s rRNA sequencing. The Gram­negative bacteria drug sensitivity plate was used for the antimicrobial susceptibility test of the isolated strains， and the whole genome was sequenced to analyze the antibiotic­resistant genotypes.Results169 strains of E.coli were isolated from 259 samples， with a detection rate was 65.25%， among which the detection rates of E.coli in chicken and pork were 77.38% and 42.86% respectively. The result of antibiotic susceptibility test showed that E.coli was highly resistant to trimethoprim­sulfamethoxazole （83.33% in chicken and 91.67% in pork）， followed by doxycycline （32.35% in chicken and 38.89% in pork）. Meanwhile， they also showed different degrees of antibiotic resistance against gentamicin， tobramycin， cefotaxime and colistin. Genotyping analysis found that β­lactam genes ampC1 and ampC2 had the highest carrying rate of 93.10% and 98.28%， respectively. In addition， multidrug resistance genotypes such as ESBL， NDM­1 and mcr­1 were also detected， among which blaTEM­1D and blaCTX­M-9 were the main ESBL resistance genes.ConclusionAt present， there is a serious E.coli contamination in raw meat in Beijing， especially in chicken. The isolated strains not only showed complex antibiotic­resistance phenotypes， but also carried a variety of antibiotic­resistance genotypes. The control of microbial contamination and bacterial drug resistance in fresh meat samples should be strengthened， especially ESBL­producing Escherichia coli， which provided a scientific basis for the prevention and control of foodborne diseases.

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