Presentations

Bordetella bronchiseptica is a widespread Gram-negative bacterium. Its role in atrophic rhinitis of pigs is very important; it causes remarkable economic loss to the modern swine industry. It also causes respiratory diseases in dogs, cats, rabbits and guinea pigs. In the recent years case reports on human infections have also been reported, thus B. bronchiseptica may implicate a zoonotic risk as well.

In our study we have focused on the incidence of B. bronchiseptica in different pets, differentiation of strains based on phenotypic and genotypic features and finding molecular marker(s) of host adaptation.

We have examined 25 strains (9 were isolated from dogs, 10 were isolated from rabbits, 4 were isolated from guinea pigs and 2 were isolated from cats). Six strains originated from dogs and 8 strains originated from rabbits were freshly isolated, the rest of the strains were selected from the strain collection of VMRI. We isolated B. bronchiseptica from the samples originated from dogs in a rate of 21% and from the samples originated from rabbits in a rate of 62%. The strains were homogeneous in biochemical analysis, whereas in the haemagglutination assay (with blood originated from different species) they were different. The strains originated from dogs did not show haemolytic activity.

PCR reaction on the cyaA gene (coding region of adenylate-cyclase haemolysin toxin) gave negative results with strains isolated from dogs. Our results were in agreement with the literature data, it is known that a number of isolates originated from dogs and human is lacking the cyaA gene. That could be useful marker of host adaptation in these cases. We have analysed the flaA (coding region of flagellin) gene with PCR-RFLP using BglI és HincII restriction endonucleases. The analysis resulted 3 different types: strains originated from dogs belonged to type 1, strains originated from cats and guinea pigs belonged to type 3, and strains originated from rabbits belonged to type 1 and 2.