[Production of a Babesia ovis extract and its testing for antigenic properties].

An extract of the parasitic erythrocyte stroma sediment of Babesia ovis was produced. Parasite infestation of the erythrocytes was from 23 to 25%. The sediment was destroyed by three methods: 1) By ultrasound; 2) by twenty-fold freezing and unfreezing in liquid nitrogen; 3) by lyophylization. The supernatant of the destroyed sediment, obtained by ultracentrifugation of 103,5000 g per 1 h was tested as antigen in RCB, RAGP, RIHA. Positive result was obtained for all three reactions with homologous antiserums of lambs immunized with live vaccine and plasmic antigen. In case heterologic anti A. ovis serum and normal sheep serum were used the result was negative. Compared to the "standard" corpuscular antigen for RCB and to the plasmic antigen the extract proved more active.