Survey of babesiosis in symptomatic dogs from Romania: occurrence of Babesia gibsoni associated with breed.

Blood samples from 49 symptomatic dogs from 5 western and north-western counties of Romania were screened using microscopic examination, polymerase-chain-reaction-restriction-fragment-length-polymorphism procedure (PCR-RFLP), and sequence analysis. Results of the microscopic evaluation of stained blood smears revealed 45 positive samples with the presence of large and small intraerythrocytic piroplasms in 35 and 10 samples, respectively. Babesia canis (35/49, 71.4%) and Babesia gibsoni (14/49, 28.6%) were identified and differentiated by PCR-RFLP targeting the 18S rRNA gene. Results of the sequence analysis of all B. gibsoni and 17 randomly selected B. canis PCR products confirmed the PCR-RFLP-diagnosed species. The distribution of B. gibsoni infection was positively associated (p<0.001) with fighting dog breeds including infection in 12 American Pit Bull Terriers and one American Staffordshire Terrier. This report is the first to present molecular evidence of the occurrence of B. gibsoni in Romania confirmed by sequencing.