Current Resistance Patterns of Bacterial Pneumonia Pathogens and Therapeutic Considerations

Abstract

A standardized test of sensitivity (following DINx 58 940) to 10 chemotherapeutic agents was conducted on 49 Pasteurella and 10 C. pyogenes strains. These strains had been isolated from nasal or pulmonary secretions of calves with bronchopneumonia or from affected lung tissue of animals that had died. Resistance rates were determined on the basis of minimal inhibitory concentration or by the disk diffusion method. These were: for erythromycin 0%, tri- methroprim/sulfadoxine 2.3%, penicillin G 20.5%, ampicillin 24.5%, kanamycin 24.5%, neomycin 32.7%, chloramphenicol 43.2%, sulfamethazine 54.5%, oxytetracycline 63.6%, and streptomycin 75.5%. C. pyogenes proved to be highly sensitive to penicillin G. Routine checking of resistance patterns is necessary for achieving effective trf* tment of bronchopneumonia.