Microbial flora and antimicrobial susceptibility patterns from dogs with otitis media

This study evaluated the middle ear microbial flora and antimicrobial susce ptibility patterns from dogs with otitis media. Antimicrobial susceptibilit y patterns were obtained on 164 micro-organisms from 107 ears of 82 dogs wi th otitis media that presented to Louisiana State University over a 12-year period. The most common micro-organisms isolated were Staphylococcus inter medius (26.8%), Pseudomonas aeruginosa (23.2%), beta -haemolytic streptococ cus (12.8%), Proteus spp. (11.0%) and Staphylococcus epidermidis (8.5%). An timicrobial susceptibility testing was performed on all isolates employing the disk diffusion method (Kirby-Bauer). Minimum inhibitory concentration ( MIC) testing for enrofloxacin and ciprofloxacin was performed on 10 of the is P. aeruginosa isolates found to be resistant to enrofloxacin on Kirby-Ba uer. Of these isolates, 6 (60%) were susceptible, 1 (10%) was intermediate and 3 (30%) were resistant to enrofloxacin. Eight of these isolates (80%) w ere susceptible to ciprofloxacin, 1 (10%) showed intermediate susceptibilit y and 1 (10%) was resistant.