Antibacterial sensitivity patterns of bacteria isolated from dogs with otitis externa

From January, 1973, to December, 1975, the most prevalent microorganisms isolated from ear swab specimens taken from 323 dogs with otitis externa were Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus spp. Comparison of the antibiograms of these isolants to those reported from England in 1961 and from the United States in 1970 suggested emergence of a greater proportion of bacterial strains with resistance to antibacterial agents commonly used to treat otitis externa of dogs.