Antimicrobial susceptibility of arcanobacterium pyogenes isolated from the lungs of white-tailed deer (odocoileus virginianus) with pneumonia

Lisa A Tell, Jason W. Brooks, Valerie Lintner, Tammy Matthews, Subhashinie Kariyawasam

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14 Scopus citations


In vitro susceptibilities of 29 strains of Arcanobacterium pyogenes isolated from lung lesions of white-tailed deer (Odocoileus virginianus) with pneumonia were determined using the broth microdilution method to ascertain efficacious treatment options for pneumonic white-tailed deer. All 29 A. pyogenes strains tested were susceptible to ceftiofur, spectinomycin, tiamulin, and trimethoprim-sulfamethoxazole but were resistant to both danofloxacin and sulfadimethoxine. Likewise, all 29 isolates were either fully susceptible or intermediately susceptible to gentamicin (25 susceptible; 4 intermediate) and tulathromycin (25 susceptible; 4 intermediate). At least one isolate of A. pyogenes tested was resistant to ampicillin, chlortetracycline, clindamycin, enrofloxacin, florfenicol, oxytetracycline, penicillin, and tilmicosin suggesting their ineffectiveness in treating A. pyogenes-associated lung infections in white-tailed deer. Minimum inhibitory concentration (MIC) data for tylosin and neomycin could not be interpreted due to unavailability of Clinical and Laboratory Standards Institute (CLSI)-approved breakpoints for these 2 agents. In summary, based on MIC values, ceftiofur, spectinomycin, tiamulin, and trimethoprim-sulfamethoxazole are more efficacious than other antimicrobial agents for treating A. pyogenes-related pneumonia in white-tailed deer. However, ceftiofur may be preferred over the other 4 drugs as it is being widely used to treat respiratory disease in cattle and other animal species, as well as is available for single dose parenteral administration.

Original languageEnglish (US)
Pages (from-to)1009-1013
Number of pages5
JournalJournal of Veterinary Diagnostic Investigation
Issue number5
StatePublished - Sep 2011



  • Antimicrobial susceptibility
  • Arcanobacterium pyogenes
  • broth microdilution
  • minimum inhibitory concentration
  • pneumonia
  • white-tailed deer

ASJC Scopus subject areas

  • veterinary(all)

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