Abstract
Adequate knowledge of the genetic diversity among
Babesia
species infecting dogs is necessary for a better understanding of the epidemiology and control of canine babesiosis. Hence, this study determined the genetic diversity among the
Babesia rossi
detected in dogs presented for routine examination in Veterinary Hospitals in Abeokuta, Nigeria. Blood were randomly collected from 209 dogs. Field-stained thin smears were made and DNA extracted from the blood. Partial region of the 18S small subunit ribosomal RNA (rRNA) gene was amplified, sequenced and analysed.
Babesia
species was detected in 16 (7.7%) of the dogs by microscopy. Electrophoresed PCR products from 39 (18.66%) dogs revealed band size of 450 bp and 2 (0.95%) dogs had band size of 430 bp. The sequences obtained from 450 bp amplicon displayed homology of 99.74% (387/388) with partial sequences of 18S rRNA gene of
Babesia rossi
in the GeneBank. Of the two sequences that had 430 bp amplicon, one was identified as
T. annulata
and second as
T. ovis
. A significantly (p<0.05) higher prevalence of
B. rossi
was detected by PCR compared to microscopy. The mean PCV of
Babesia
infected dogs was significantly (p<0.05) lower than non-infected dogs. Phylogenetic analysis revealed minimal diversity among
B. rossi
with the exception of one sequence that was greatly divergent from the others. This study suggests that more than one genotype of
B. rossi
may be in circulation among the dog population in the study area and this may have potential implication on clinical outcome of canine babesiosis.