CHARACTERISTIC GENOTYPES DISCRIMINATE BETWEEN BABESIA-CANIS ISOLATES OF DIFFERING VECTOR SPECIFICITY AND PATHOGENICITY TO DOGS

The first and second internal transcribed spacers (ITS1, ITS2) as well as the intervening 5.8S coding region of the rRNA gene were character ized in eight Babesia canis isolates of differing geographic origin, v ector specificity; and pathogenicity to dogs. The genotypes determined by sequencing segregated into three clearly separated groups close to or near the species level and correspond to the previously proposed s ubspecies B. canis canis, B. canis vogeli, and B. canis rossi. The thr ee genotypes can be distinguished by Sau96I digestion of the polymeras e chain reaction (PCR)-amplified rDNA target.