The capsular serogroupes and drug susceptibility of 111 isolates of Pasteurella multocida from pigs with atrophic rhinitis and pneumonic lesions were investigated.
Of the 111 P multocida isolates, 42 were from lung lesions, 47 from nasal turbinate lesions and the remaining 22 from the nasal swabs. P multocida isolates were typed for capsular serogroupes A by hyaluronidase inhibition of capsule and D by acriflavine auto-agglutination. Most isolates(64.9%) were type A, 23.4% were type D and the remaining 11.7% were untypable.
Resistance to triple sulfa(97.3%) was most frequent, followed by resistance to tiamulin(71.2%), tylosin(56.8%), streptomycin(36.9%), and neomycin(36.0%). The majority of the organisms were susceptible in order of prevalence to baytril(100%), ampicillin(98.2%), linsmycin(97.3%), colistin(97.3%), cephalothin(94.6%), gentamicin(93.7%), amikacin(92.3%), tetracycline(91.9%), trimethoprim/sulfamethoxazole(91.0%), and kanamycin(90.1%).
No differences in drug resistance in relation to capsular serogroupes of P multocida and the origin of lesions were noted. A high prevalence of multiple drug resistance was observed and the most common resistant patterns were Sss, Tm, Ty(12.6%) and Sm, Sss, Tm, Ty(8.1%) patterns.
|