TDK conference 2016

The oral hygiene in dogs depends mostly on the quality of food consumed and plaque removal performed by the owner. In neglected cases severe, irreversible periodontitis with pockets containing anaerobic bacterial flora could evolve in months or years. The aim of this study was to isolate Porphyromonas spp. and Prevotella spp. from subgingival samples taken from dogs with moderate to severe clinical periodontal diseases, and the susceptibility testing of these strains, with special regard to pradofloxacin.

Samples for the study were collected while the dogs were under general anaesthesia. We collected 150 periodontal samples from 59 dogs. Periodontal pockets were swabbed with absorbent paper points, as deep as possible. Paper points were placed immediately in an anaerobic transport tube containing transport medium and the tubes were shipped directly to DUO-BAKT LABORATÓRIUM, Budapest, Hungary. At DUO-BAKT LABORATÓRIUM the samples were transferred to an anaerobic culturing process: each paper point was inoculated on a Wilkins-Chelgreen (incl. 8% sheep blood) plate and on another plate which included nalidixic acid and colistin. All plates were incubated in an anaerobic environment at 35°C for 5-7 days, after which all pigmented colonies and the suspected non-pigmented Prevotella spp. colonies were selected. The identification was performed by analyzing the morphology of the colonies, pigmentation, and the results of the presumptive tests. Final identification was performed by MALDI-TOF-mass spectroscopy.

During the study, 74 Porphyromonas spp. and 2 Prevotella spp. strains were isolated, identified and transported to Laboklin, Bad Kissingen, Germany for susceptibility testing. According to our results, pradofloxacin could be a promising choice in the treatment of periodontitis as in most cases the MIC concentrations were under 0.1 mg/l. Based on our clinical experiences and the MIC concetrations, amoxicillin-clavulanic-acid is still an appropriate antibiotic for the treatment of periodontal diseases in dogs, however, resistant strains to clindamycin and metronidazol were found. These susceptibility test results could help veterinarians to create the best protocols for the treatment of periodontitis.