By means of the enzyme-linked immunosorbent assay (ELISA), antibodies to Borrelia burgdorferi were examined in 970 cattle from southern Hokkaido, Japan. The seropositivity rate in the cattle less than 2 years old differed significantly from that in those 3 years old or more. A seasonal variation was also observed in the rate of seropositivity to B. burgdorferi. High levels of anti-B. burgdorferi antibody were detected even in sera from a healthy group of cattle, indicating that there are likely to be many inapparent cases of B. burgdorferi infection. This article discusses the syndromes associated with
Lyme borreliosis and addresses the issues of diagnosis and treatment in animals.