More than half of the 160 Bernese mountain dogs examined by researchers from the University of Zurich, Switzerland, tested positive for the spiral-shaped bacteria Borrelia burgdorferi, compared with only 15 percent of the 62 control dogs, which were not of Bernese descent but of comparable size and coat length.
Using the enzyme-linked immunosorbent assay (ELISA) and a Western blot test, the Swiss researchers found that 58 percent of the Berners had developed antibodies against B. burgdorferi.
Neither living in rural areas where ticks might be more prevalent noire more frequent walking explained the dogs’ tendency to acquire the bacteria, according to lead researcher Dr. Bernhard Gerber. Neither did its dark coat color; researchers assume darker coats make it harder for dog owners to spot ticks before they burrow in.
Although the scope of the study did not allow them to explore the biological reasons behind the infection rates or the possible consequences for the dogs, Gerber did say they suspect a breed predisposition to the bacteria in Bernese.
The study was published July 11 in the online journal BMC Veterinary Research.