Abstract:
In this study, asymptomatic dogs in nine provinces of Turkey were surveyed to investigate
the prevalence and intensity of Hepatozoon canis infection. DNA obtained from blood
samples collected from 694 domestic dogs (243 stray, 288 shelter, and 163 pets) of both
genders and varying ages were evaluated by polymerase chain reaction (PCR). In addition,
285 thin blood smears prepared from these blood samples were also evaluated for
microscopic examination. Direct microscopy revealed Hepatozoon gamonts in the peripheral
blood of three of 285 (1.0%; 95% confidence interval (CI): 0.21–3.04) tested. Using PCR,
155 of the 694 (22.3%; 95% CI: 19.28–25.61) were found to be positive for the presence of H.
canis DNA. The prevalence of infection was higher in adult dogs (26.2%; 95% CI: 22.1–30.7)
than young animals (16.4%; 95% CI: 12.2–21.3). Although the prevalence determined by
PCR was higher in male dogs (24.5%; 95% CI: 19.6–29.9) than in female dogs (20.8%; 95%
CI: 16.9–25.1), gender differences were not significant. Pet dogs had a lower prevalence of
infection (10.4%; 95% CI: 6.2–16.2) compared to stray (26.3%; 95% CI: 20.9–32.3) and shelter
dogs (25.7%; 95% CI: 20.7–31.1), but no significant association between stray and shelter
dogs was found for the presence of the parasite. Partial sequences of the 18S ribosomal RNA
(rRNA) gene shared 99–100% similarity with the corresponding H. canis isolates. This epidemiological
survey revealed a high prevalence of H. canis in dogs from several provinces
in Turkey, and it suggests that the age and origin are associated with the parasite.
