Effect of passive immunoglobulin transfer on results of diagnostic tests for antibodies against Borrelia burgdorferi in pups born to a seropositive dam.

The event that 8 of 12 pups born to a Lyme borreliosis-positive dam tested positive on a commonly used in-hospital Lyme borreliosis test kit at 1 week of age prompted breeder concern about the possibility and implications of transplacental Lyme borreliosis infection. Almost 2 weeks after the initial serologic test results were obtained, blood was collected from the puppies for comprehensive testing. Assessment of the findings indicate the possibility that passive transfer of maternally derived antibody to the in vivo expressed C6 peptide of Borrelia burgdorferi can temporarily render pups serologically positive for antibodies on the in-hospital C6 Lyme borreliosis antibody test kit when the test is run on very young animals.