DIFFERENT BABESIA-CANIS ISOLATES, DIFFERENT DISEASES

Using surface immunofluorescence isolate-specific antigens were detect ed on the membrane of erythrocytes infected with Babesia parasites. In addition, the strains reacted differently with Plasmagel in that the European isolate (B.c, canis) could be purified on Plasmagel effective ly, whereas infected erythrocytes of the South-African isolate (B.c. r ossi) could not. Experimental infection of dogs with Babesia canis iso lates from geographically different areas revealed different pathology . The European isolate obtained from France exhibited transient parasi taemia, usually below 1 %, associated with low PCV values and congesti on of internal organs. Clinical disease was correlated with an effect on the coagulation system, and not with peripheral parasitaemia. Infec tion of dogs with South-African-derived isolate induced high parasitae mia usually much higher than 1 %, which required chemotherapeutic trea tment. In these animals clinical disease was correlated with periphera l parasitaemia and not with parameters of the coagulation system. The results show that the etiology of disease caused by these isolates of B.c. canis and B.c. rossi is different. This might have implications f or the development of vaccines against these infections.