Phenotypic and Genotypic Characterisation of Pasteurella Multocida Strains Isolated from Pigs in Poland
AbstractA total of 319Pasteurella multocida(Pm) strains isolated from pigs in Poland were examined. Phenotypic characterisation included: biochemical tests (to determine species, subspecies, and biovar), capsular typing, and antimicrobial susceptibility. Genotypic characterisation included detection of thetoxAgene by PCR. All testedPmstrains were classified asPmsubsp.multocida: 87.2% biovar 3, 10.7%-2 and 0.9%-12. One strain was classified as biovar 1. Three strains ofPmdid not suit any of the biovars. Using capsular typing methods, 77% ofPmstrains isolated from nasal swabs belonged to type D and 33% to type A. AmongPmstrains isolated from internal organs, 59.5% belonged to type A and 40.5% to type D. All the isolates showed a high susceptibility to β-lactams: ampicillin and amoxicilin with clavulonic acid (97.8%), penicillin (86.7%), doxicilline (100%), oxytetracycline (97.8%), and tetracycline (93.2%). It was found that all strains were susceptible to norfloxacin, 97.8% to enrofloxacin, and 95.6% to SxT. 24.4% and 15.6% of the strains were resistant to linco-spectin and tiamulin, respectively. The presence oftoxAgene was confirmed by PCR in 20.8% of the strains isolated from nasal swabs and 29.1% of isolates from internal organs.