Carriage rate and antibiotic susceptibility of coagulase-positive staphylococci isolated from healthy dogs in Victoria, Australia.
BACKGROUND
Studies in Australia and elsewhere have shown high levels of antibiotic resistance in coagulase-positive staphylococci in dogs visiting veterinary clinics with pyoderma and related conditions. Although important, such studies tend to overestimate the burden of resistance. The aim of the current study was to investigate the prevalence of coagulase-positive staphylococci in healthy dogs in Central Victoria to assess the level of antibiotic resistance among these isolates.


METHODS
We recruited 117 healthy dogs into the study. Swabs were taken at four sites (ear, mouth, nose, perineum) and staphylococcal species identified and isolated using culture and biochemical techniques.


RESULTS
Staphylococcus pseudintermedius and S. aureus were recovered from 100 and 17 dogs, respectively; 15 dogs were simultaneously co-colonised with both organisms. The mouth and perineum were the most sensitive sites for recovery of these organisms. The most commonly encountered resistances were penicillin (95.2% and 72.4% in S. aureus and S. pseudintermedius, respectively) and doxycycline/tetracycline (19.7% in S. pseudintermedius). No methicillin-resistant S. aureus were recovered, but two phenotypically methicillin-resistant S. pseudintermedius (MRSP) isolates were recovered, although only one was PCR-positive for the mecA gene. Notably the MRSP isolate was multidrug resistant, as it also exhibited resistance to mupirocin and erythromycin.


CONCLUSIONS
With the exception of penicillin, doxycycline and tetracycline, the level of resistance to the antimicrobial agents tested was minimal. Prudent antibiotic use in treating companion animals with skin infections will reduce the selection of MRSP and other multidrug-resistant bacteria.
Federation University Australia, Faculty of Science & Technology, PO Box 663, Ballarat, Victoria 3353, Australia.
D C
http://orcid.org/0000-0003-4684-6936
DC
Bean
Federation University Australia, Faculty of Science & Technology, PO Box 663, Ballarat, Victoria 3353, Australia.
S M
SM
Wigmore
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004285:Dogs / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D004423:Ear / Q000382:microbiology; D009055:Mouth / Q000382:microbiology; D009666:Nose / Q000382:microbiology; D010502:Perineum / Q000382:microbiology; D013203:Staphylococcal Infections / Q000382:microbiology / Q000662:veterinary*; D013210:Staphylococcus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D014739:Victoria / Q000453:epidemiology
D000900:Anti-Bacterial Agents
antimicrobial resistance; dogs; pyoderma