Comparison of the phenotypic antimicrobial resistances and spa-types of methicillin-resistant Staphylococcus aureus (MRSA) isolates derived from pigs in conventional and in organic husbandry systems

Berl Munch Tierarztl Wochenschr. 2014 Mar-Apr;127(3-4):135-43.

Abstract

The purposes of this study were to identify differences in the phenotypic resistance to antimicrobials and in the spa-types between 273 methicillin-resistant Staphylococcus aureus (MRSA) isolates derived from conventional (n = 21) versus organic pig farms (n = 10) located in Germany. The susceptibility of the isolates against 19 antimicrobial agents was tested and then compared between the two different husbandry systems. A statistically significant difference was observed between the MRSA strains isolated on conventional and on organic pig farms for the antimicrobials tilmicosin (61.8% vs. 40.0%; OR: 2.42), clindamycin (63.5% vs. 45.7%; OR: 2.06), gentamicin (14.7% vs. 34.3%; OR: 0.33), apramycin (3.8% vs. 22.9%; OR: 0.13) and enrofloxacin (13.9% vs. 34.3%; OR: 0.31). Finally, the results of the susceptibility testing were analysed in order to determine the resistance pattern per isolate. Among the tested isolates a kind of"basic resistance pattern of MRSA"to penicillin, ampicillin and tetracycline was identified. The predominant spa-types in both groups were t011 and t034. Less frequently detected spa-types were t1430, t1197, t2510, t779, t1451 and t1250.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animal Husbandry*
  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Cross-Sectional Studies
  • Environmental Microbiology
  • Female
  • Male
  • Methicillin-Resistant Staphylococcus aureus / classification
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Methicillin-Resistant Staphylococcus aureus / genetics*
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification
  • Microbial Sensitivity Tests
  • Molecular Typing
  • Nasal Cavity / microbiology
  • Phenotype
  • Staphylococcal Infections / microbiology*
  • Staphylococcal Infections / veterinary*
  • Staphylococcal Protein A / genetics
  • Swine
  • Swine Diseases / microbiology*

Substances

  • Anti-Bacterial Agents
  • Staphylococcal Protein A