Isolation and characterization of a Babesia species from Rhipicephalus evertsi evertsi ticks picked off a sable antelope (Hippotragus niger) which died of acute babesiosis.

Transmission of a Babesia species to susceptible cattle by Rhipicephalus evertsi evertsi ticks picked off a sable which died of acute babesiosis is described. The parasite was initially isolated by feeding R. e. evertsi ticks on a susceptible, splenectomised bovine which developed parasitaemia. Blood stabilate from the parasitaemic bovine produced a fatal babesiosis in a spleen--intact bovine. Clinical signs shown by the affected animals corresponded with those of acute babesiosis. Parasitological examination, the immunofluorescence antibody test and the polymerase chain reaction test revealed that the parasite transmitted by the ticks initially and the blood stabilates prepared from affected animals was Babesia bigemina. This parasite was morphologically identical to that observed in Giemsa-stained blood smears prepared from the dead sable.