Detection of ehrlichial antigen in plasma of beagle dogs with experimental acute Ehrlichia canis infection.

Six beagles were experimentally infected with Ehrlichia canis. All dogs developed typical clinical signs of ehrlichiosis and sero-converted. Ehrlichial antigenemia in the plasma of the infected dogs was detected using a sandwich enzyme-linked immunosorbent assay (ELISA). Ehrlichial antigen was present starting 15-20 days post-infection, after the development of clinical signs and antibody titre to Ehrlichia canis. The appearance of ehrlichial antigen in the plasma for a relatively short and variable period after the clinical and haematological signs, limits its potential as an early diagnostic prognosticator of canine ehrlichiosis.