Background
Lawsonia intracellularis is an obligate intracellular bacterium which cannot be cultured by conventional bacteriological
Conclusions
This is the first report of isolation of L. intracellularis strains from South America and Southeast Asia and characterization of the antimicrobial susceptibility patterns of these new strains.
Results
Two strains from Brazil and three strains from Thailand were successfully isolated and established in cell culture. Each antimicrobial was evaluated for intracellular and extracellular activity. Pleuromutilin group (valnemulin and tiamulin) and carbadox were the most active against L. intracellularis strains tested. Tylosin showed intermediate activity, chlortetracycline had variable results between low and intermediate activity, as well as spectinomycin, spectinomycin and lincomycin, amoxicillin, sulfamethazine and enrofloxacin. L. intracellularis was resistant to lincomycin, gentamicin, trimethoprim, colistin and bacitracin in in vitro conditions. Conclusions: This is the first report of isolation of L. intracellularis strains from South America and Southeast Asia and characterization of the antimicrobial susceptibility patterns of these new strains.