IDENTIFICATION OF SALMONELLA-ABORTUSOVIS BY PCR AMPLIFICATION OF A SEROVAR-SPECIFIC IS200 ELEMENT

Field and collection isolates of Salmonella abortusovis carry one IS20 0 element in a distinct chromosome location, IS200 is not found in the corresponding region of the chromosome of other Salmonella serovars. Sequencing of the boundaries of the S. abortusovis-specific IS200 inse rtion permitted the design of primers for the amplification of this IS 200 element by PCR. Isolates of S. abortusovis are identified by the a mplification of a DNA fragment of about 900 bp or larger, PCR amplific ation of DNA from salmonellae other than S. abortusovis yields either a fragment of about 200 bp or no product, The high specificity of the assay is confirmed by the absence of cross-reactivity with the followi ng templates: (i) sheep DNA, (ii) DNAs from abortion-causing agents ot her than S. abortusovis, and (iii) DNAs from microorganisms that do no t cause abortion but are common in flocks.