EXPERIMENTAL-INFECTION WITH EHRLICHIA-PHAGOCYTOPHILA AND BABESIA-DIVERGENS IN CATTLE

Nine Norwegian Red Cattle, 9-12 months old, were inoculated simultaneo usly with Ehrlichia (Cytoecetes) phagocytophila and Babesia divergens. Ten cattle of the same breed and age were kept as controls. Clinical evaluation was done on a daily basis and rectal temperatures were reco rded every morning for 4 weeks post inoculation. Blood and serum sampl es were collected regularly during the observation period. Sera were e xamined for the presence of antibodies to E. phagocytophila and B. div ergens by an indirect immunofluorescence antibody lest. All infected a nimals showed two periods of fever that corresponded to the proliferat ion of B. divergens and E. phagocytophila in the peripheral blood. The simultaneous infection did not induce more severe clinical symptoms t han infection with either organism alone. Compared with the control gr oup, there was a 25 % decrease in the mean haematocrit. The leukogram showed a biphasic pattern and corresponded to the changes seen in infe ction with either organism alone. The simultaneous infection did nor s uppress antibody formation towards E. phagocytophila or B. divergens.