Abstract
Seven species within the genus Brachyspira have been described. This genus belongs to the bacterial phylum Spirochaetes. The most well-known species in veterinary medicine are B. hyodysenteriae and B. pilosicoli, which cause swine dysentery and porcine intestinal spirochetosis. It has also been shown that some Brachyspira spp. cause enteric diseases in birds. Dogs can harbour several different variants of brachyspiras and at least one of them is of clinical significance. Humans carry different variants of B. aalborgii and B. pilosicoli. The latter can cause enteric problems in humans and may be a zoonotic agent. Species identification is usually done by biochemical metods or PCR. Sequence analysis of the 16S rRNA gene is very useful for studies of the biodiversity of brachyspiras, because in spite of the fact that the organisms form a coherent phylogenetic cluster with relatively few sequence differences, there exist a number of sequence variants within each species. We will establish which sequence variants occur in, among other species, wild and domesticated birds to try to understand their significance for pathogenicity and as a reservoir. We have found new biochemical variants of Brachyspira sp. and these will be characterized by sequence anlysis of the 16S rRNA gene and other molecular methods. The aim of the project is to establish the significance of biodiversity for pathogenicity within the genus Brachyspira and, therefore, experimental infections have to be done.
Sweden