Genetic diversity and associated pathology of Pasteurella multocida isolated from porcine pneumonia

Abstract

Pasteurella multocida is a widespread respiratory pathogen in pigs associated with atrophic rhinitis and contributing to aggravation of the pulmonary lesions. The aims of the present study were to characterize isolates of P. multocida from porcine bronchopneumonia by pulsed-field gel electrophoresis (PFGE), PCR based capsular typing and multilocus sequence typing (MLST) and to compare clonal complexes outlined with the type of histological lung lesions to investigate if a correlation between clonal lineages and lesions might exist. Isolates of P. multocida were obtained from cases of cranioventrally located porcine bronchopneumonia. All lung lesions were described and classified according to histological lesions. A total of 139 isolates, from lung (n=111), pericardial sac (n=21) and kidney (n=7) of 111 pigs were described using PFGE with ApaI as the restriction enzyme. Furthermore, 20 and 29 isolates were characterized by capsular serotyping and multilocus sequence typing, respectively. PFGE demonstrated 15 different clusters showing 50% or more similarity. All selected isolates were of capsular serotype A and only three main sequence types (ST) were detected among the isolates. Associations were not found between histopathology and clonal complexes of P. multocida. In conclusion, PFGE demonstrated a high diversity of genotypes of P. multocida associated with porcine bronchopneumonia. However, isolates obtained mainly belonged to few STs, indicating that isolates of P. multocida associated with porcine bronchopneumonia originates from a limited number of clonal lineages and therefore might have adapted to porcine hosts. No correlation was demonstrated between genotypes and types of lesions, and extra-pulmonary spreading was only rarely demonstrated.

Molecular characterization of Pasteurella multocida isolates from swine lungs by Randomly Amplified Polymorphic DNA

“…Cluster V contained isolates from two complexes, ST13 from Sorriso and ST74 from Campo Grande. Most of the isolates from this study belong to ST74 and ST13, which was similar to swine in Norway (PORS et al, 2011), except that ST50 was absent in our study. These isolates are probably species-specific (HOTCHKISS et al, 2011) with the exception of ST13, which has also been identified in cattle.…”

Aspectos patológicos e microbiológicos das doenças respiratórias em suínos de terminação no Brasil

“…Porém, o número de amostras analisadas foi baixo, o que deve ser considerado na interpretação deste achado. Esse resultado pode ser explicado pela alta variabilidade antigênica entre as amostras de P. multocida isoladas de suínos (Pors, et al, 2011;Bethe et al, 2009).…”

The Prevalence of Pasteurella Multocida from Farm Pigs in Serbia

“…Choi et al (15) report a prevalence of coinfection with PRRS and P. multocida to be 10.4%, PRRS and M. hyopneumoniae of 7% and PRRS and A. pneumoniae to be 6.2%. Also, the mixed infections have been described in several studies (16,17,18,19). In these studie,s the more common mixed infections were P. multocida with viruses or bacterial agents.…”