1996 Volume 49 Issue 2 Pages 81-84
The nasal swabs from bovine pneumonic cases were bacteriologically examined from 1986 to 1995. One hundred and forty isolates of Pasteurella multocida, 23 of P. haemolytica, 137 of Mycoplasma bovis, 76 of M. bovirhinis and 104 of Ureaplasma diversum were obtained from 271 out of 329 (82.4%) cases. Of 271 cases, 105 (38.7%) were of mixed infection with Pasteurella and Mycoplasma and/or U. diversum. The Pasteurella isolates had high sensitivity to enrofloxacin (ERFX) and ampicillin, showing a minimum 50% inhibitory concentration (MIC50) of≤0.10μg/ml. Mycoplasmas had high sensitivity to ERFX, tylosin and lincomycin, showing an MIC50 of≤0.78μg/ml. On the other hand, susceptibility of Pasteurella and Mycoplasma to thiamphenicol and oxytetracycline was extensively variable, suggesting common distribution of the resistant strains to these drugs.
