Identification of ureaplasmas from cattle using antisera prepared in gnotobiotic calves.

Antisera were prepared in gnotobiotic calves to three bovine ureaplasma strains which were selected as representatives of the three clusters of serologically similar, but not identical, strains recognized in previous experiments with rabbit antisera. A further 110 isolates from various organ systems of cattle from six countries reacted by the fluorescent antibody technique with at least one of these bovine antisera and it appears that bovine ureaplasmas can be identified and classified by means of three antisera only. It is suggested that the bovine ureaplasmas could be designated as groups A, B or C, these being further subdivided with rabbit antisera. These findings make possible the screening of cattle for antibody to ureaplasmas with just three antigens and also have implications for immunization.