Occurrence of Genes Encoding Virulence Factors in Bordetella Bronchiseptica Strains Isolated from Infected and Healthy Pigs

Abstract

The objective of the study was to determine genotypic profiles of Bordetella bronchiseptica (Bbr) strains, based on the occurrence of genes encoding virulence factors, such as flagella (fla), dermonecrotoxin (dnt), and exogenous ferric siderophore receptor (bfrZ), using PCR. 209 tested Bbr strains were obtained from Polish swine herds with different health status (with progressive atrophic rhinitis -PAR, suspected for PAR, and unknown). In total, seven different Bbr genotypes were determined. In 39.2% of Bbr isolates all three genes were present. In 41.1% of the isolates only two genes were detected. The most common genotype dnt+bfrZ-fla+ was present in 60 (28.5%) Bbr strains, 65% of them were obtained from farms with PAR. Twenty five (12%) Bbr isolates were identified as dnt-bfrZ+fla+ genotype and, as above, they were more frequently isolated from clinical cases of disease (84%). Among 31 (14.8%) strains only fla gene was evident, and in nine (4.3%) only dnt gene was present. There were no Bbr strains with bfrZ gene only. These results confirm the heterogenicity among Bbr strains.

Phenotypic and genotypic characterization of Bordetella bronchiseptica strains isolated from pigs in Poland

“…The presence of fla, dnt and bfrZ genes in 94.7%, 72.7% and 51.5% respectively in Bbr strains confirm a high level of pathogenictity among Polish Bbr isolates. It is suggested that fla, dnt and bfrZ genes can be use as markers of pathogenicity of Bbr strains (Stępniewska and Markowska 2012).…”

Characterization of a Unique Bordetella bronchiseptica vB_BbrP_BB8 Bacteriophage and Its Application as an Antibacterial Agent

“…In pigs, an infection with B. bronchiseptica alone usually leads to mild, nonprogressive atrophic rhinitis (NPAR). A mixed infection with both B. bronchiseptica and P. multocida results in progressive atrophic rhinitis (PAR) [12]. Whereas dermonecrotic toxin produced by P. multocida is the main factor behind the observed damage in pigs, the presence of B. bronchiseptica promotes the rate of nasal cavity colonization by the toxigenic bacterium [13].…”