Abstract: The invention relates to a Piroplasmid protein or an immunogenic fragment of said protein, and to a nucleic acid encoding said Piroplasmid protein or said immunogenic fragment. Furthermore, the invention relates to cDNA fragments, recombinant DNA molecules and live recombinant carriers comprising said nucleic acid. Also the invention relates to host cells comprising said cDNA fragments, recombinant DNA molecules and live recombinant carriers. Finally, the invention relates to vaccines comprising a Piroplasmid protein or an immunogenic fragment of said protein, to methods for the preparation of such vaccines, to the use of such proteins or fragments for vaccine purposes, and to diagnostic tests.