High prevalence of antibiotic resistance in pathogenic foodborne bacteria isolated from bovine milk

Sci Rep. 2022 Mar 9;12(1):3878. doi: 10.1038/s41598-022-07845-6.

Abstract

This study aimed to investigate the prevalence of foodborne pathogenic bacteria in bovine milk, their antibiogram phenotype, and the carriage of antibiotic resistance genes. Raw bovine milk samples (n = 100) were randomly collected from different suppliers in the northwest of Iran. Antibiotic-resistant patterns and the presence of antibiotic resistance genes were evaluated in the isolates. Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Salmonella spp. were isolated from 78%, 47%, 25%, and 21% of samples, respectively. All isolates showed high rates of resistance to amoxicillin, penicillin, and cefalexin. The blaTEM and blaSHV genes were detected in 50.0% and 6.4% of E. coli isolates, respectively. Also, 28.5% and 19.0% of Salmonella isolates were positive for blaTEM and blaSHV. The frequency of mecA and blaZ in S. aureus isolates was 20.0% and 12.0%, respectively. The high prevalence of bovine milk contamination with antimicrobial-resistant species in this study necessitates precise control on antibiotic prescription in veterinary medicine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Drug Resistance, Bacterial / genetics
  • Escherichia coli
  • Listeria monocytogenes*
  • Microbial Sensitivity Tests
  • Milk* / microbiology
  • Prevalence
  • Salmonella / genetics
  • Staphylococcus aureus

Substances

  • Anti-Bacterial Agents