Abstract

We isolated a novel, unknown Brucella species from a minke whale (Balaenoptera acutorostrata) that had been caught during commercial hunting off the Norwegian coast of Finnmark in May 1995. Cultural characteristics, agglutination and biochemical tests are consistent with the diagnosis of a smooth Brucella sp. DNA work has shown positive PCR results for the specific Brucella 16S-23S Spacer and IS65O1 sequences. RFLP studies based on the IS6501 sequence showed a unique profile in comparison to those described for the recognised Brucella species. Moreover, Southern Blot analysis, as well as the sequencing of the omp2 locus, has shown a unique characteristic: the minke whale Brucella appears to have two copies of the omp2b gene. This strain is the first known Brucella strain that has 2 copies of the omp2b gene. This is the first description of a Brucella sp. in rorquals. The isolation of a novel agent that is potentially responsible for reproductive disorders in baleen whales, as well as its potential zoonotic importance, is of concern. Finally, the isolation of Brucella sp. in whales, seals, dolphins and porpoises raises questions regarding the source(s) of infections and the phylogenetic link between the Brucella species found in marine mammals and domestic mammals.