In vitro antibiotic sensitivity of French strains of Mycoplasma bovis

: The in vitro activity of 15 antibiotics was tested with 30-90 Mycoplasma bovis representative strains of bovine lung pathology in France. The distribution of minimal inhibitory concentration (MIC) is homogeneous with low values for spectinomycin, lincomycin, tylosin, gentamicin and baytril, intermediate for chloramphenicol and neomycin, high for nalidixic acid, Flumequine and erythromycin. The MIC distribution is heterogeneous with intermediate values for spiramycin and tetracyclines, and high values for streptomycin. For the later antibiotics, the heterogeneity of the susceptibility suggests a mechanism of acquired resistance.