THE DETECTION OF ANTIBODIES CROSS-REACTING WITH COWDRIA-RUMINANTIUM IN THE SERA OF DOMESTIC RUMINANTS IN REGIONS OF SOUTH-AFRICA WHERE AMBLYOMMA-HEBRAEUM DOES NOT OCCUR

High levels of seropositivity, in all probability attributable to Ehrl ichia, were recorded in the serum of domestic ruminants throughout dis tricts in South Africa where Amblyomma hebraeum, the vector of the hea rtwater agent, does not occur, The antibodies, detected with the indir ect fluorescent antibody (IFA) and the indirect ELISA tests, cross-rea cted with Cowdria ruminantium, which was used as antigen in both tests . A combination of the IFA and ELISA tests, currently employed to dete ct antibodies to C. ruminantium, facilitates the handling of appreciab le numbers of sera and ensures maximum reliability.