Molecular detection and hematological changes in dogs naturally infected by Babesia vogeli in metropolitan region of Rio de Janeiro

Rosa, CEP 24220-000, Niterói (RJ), Brasil E-mail: renataqassad@yahoo.com.br Abstract Canine babesiosis, one of the most prevalent tick-borne diseases worldwide, is an endemic disease in Brazil that has been detected in several locations. Anemia and thrombocytopenia are the most common hematologic changes in dogs with babesiosis. The aim of this study was to assess the prevalence of piroplasms, and hematological changes found in dogs in a metropolitan region of Rio de Janeiro served by the Small Animals Veterinary Hospital of the Federal Rural University of Rio de Janeiro. The 18S rRNA gene was amplified by polymerase chain reaction (PCR) and sequence-based genetic characterization was performed. Of the total 250 blood samples that were randomly analyzed, nine (3.6%) were positive for Babesia spp. Samples identified as positive for piroplasms by PCR were sequenced and Babesia vogeli was detected. The predominant hematological changes in piroplasm-positive dogs included anemia and thrombocytopenia, which were observed in six (66.7%) and eight (89%) dogs, respectively. The findings indicate that B. vogeli was the predominant piroplasm in most of the affected dogs in the studied metropolitan region. Piroplasm can cause The development of anemia in piroplasmosis is multifactorial and results from both intra and extravascular causes (Ayoob et al., 2010). Anemia was observed in 66.7% of the piroplasm-positive animals in this study. anemia, anisocytosis and polychromasia, leukopenia, lymphopenia, and thrombocytopenia in most animals.