Bernese Mountain Dogs prone to Borrelia burgdorferi infection

Dr Bernhard Gerber and colleagues from the University of Zurich, Switzerland rounded up 160 Bernese Mountain Dogs and 62 control dogs, predominantly from other longhaired, large breeds. They asked owners about their dog’s exposure to rural walks and the number of ticks attached to the dogs. The team used an enzyme-linked immunosorbent assay (ELISA) as well as a Western blot test to see whether the dogs had developed antibodies against B. burgdorferi.

Of the Bernese Mountain Dogs, 58 percent had developed antibodies against B. burgdorferi, compared with only 15 percent of the control dogs. Factors such as living in a rural area or coat colour did not explain the result, leading the authors to conclude that the breed may be predisposed to B. burgdorferi infection.

The authors data did not allow them to reach any conclusions regarding speculation that glomerular disease found in Bernese Mountain Dogs may be caused directly by B. burgdorferi, and the high incidence of B. burgdorferi infection may mean it coincides with glomerulonephritis without being the cause of the disease.

The Bernese Mountain Dog is a farm dog and originally came from Berne in Switzerland. The dogs are known for intense breeding and their narrow gene pool, which makes them especially susceptible to diseases such as epilepsy, bleeding and cancers.

However Gerber says that “the findings in the present study are unique as infections with B. burgdorferi are not causing disease”, whereas other breeds with a predilection for an infectious disease become sick. The biological reasons behind infection with the bacteria and the consequences for Bernese Mountain Dogs are currently unknown.