Identification of leptospires of the Pomona and Grippotyphosa serogroups isolated from cattle in Zimbabwe.

Two strains of the genus Leptospira, isolated from kidneys of oxen slaughtered in Zimbabwe, one belonging to serogroup Pomona (strain SBF 8) and the other to serogroup Grippotyphosa (strain SBF 32), were identified by using cross-agglutinin absorption, monoclonal antibody, restriction fragment length polymorphism and polymerase chain reaction analyses. The identification of the two strains was equivocal. Strain SBF 8 showed a close similarity to both serovars mozdok and proechimys by cross-agglutinin absorption tests and to serovar pomona by monoclonal antibody analysis, but had a distinct DNA restriction pattern. Strain SBF 32 showed a close antigenic similarity to serovars ratnapura, grippotyphosa and valbuzzi by the cross-agglutinin absorption test, and to serovar ratnapura by monoclonal antibody analysis but also had a distinct DNA restriction pattern. Both strains SBF 8 and SBF 32 reacted as members of species Leptospira kirschneri by the polymerase chain reaction. It is concluded that strains SBF 8 and SBF 32 represent new genetic strains in the Pomona and Grippotyphosa groups, respectively.