Aims: Staphylococci are considered commensal organisms; however, they can also cause diseases in animals. The species Staphylococcus pseudintermedius was originally isolated from the nares and anal mucosa of healthy dogs; nowadays, the incidence of methicillin-resistant S. pseudintermedius strains in dogs has increased, and this species has also become the most common cause of canine skin lesions. S. pseudintermedius were tested for their susceptibility to bacteriocins to show the potential of bacteriocins to eliminate/reduce S. pseudintermedius as a causative agent. Material and Methods: In this study, S. pseudintermedius were isolated from skin lesions on dogs of various breeds and ages in the Vojvodina region (Serbia) in the framework of our international co-operation. Results: S. pseudintermedius strains were identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry, and the species allocation was confirmed by genotypization and corroborated using phenotyping tests. The strains were multiresistant, involving methicillin-resistance. In addition, the mecA gene was detected in S. pseudintermedius strains, confirming the presence of a genetic feature for methicillin resistance. S. pseudintermedius strains produced large amounts of the enzymes alkaline phosphatase and acid phosphatase; they were low-grade biofilm forming (0.1 ≤ A570 < 1.0), except S. pseudintermedius SPs1. All strains were susceptible to gallidermin (inhibition activity up to 204,800 arbitrary unit [AU]/mL); however, they were mostly resistant to enterocins. However, biofilm-forming S. pseudintermedius SPs1 was susceptible to enterocins (200 AU/mL). Conclusion: Establishing the susceptibility of multiresistant and mecA gene-possessing S. pseudintermedius strains to gallidermin is an innovative, original result; it provides a new opportunity for preventing/eliminating infection caused by those agents.
Keywords: bacteriocins; dogs; ear; lesions; skin; staphylococci.