Dirofilariasis is a zoonotic parasitic disease, which its cause Dirofilaria immitis, a nematode transmitted by insects and a worldwide dissemination. Dogs and cats are the main hosts of this parasite. Therefore, this study was conducted to determine the prevalence of D. immitis in shepherd and stray dogs in Iranshahr city, southeast of Iran. In this study 49 shepherd dogs and 50 stray dogs selected randomly and the blood samples were taken and sent to parasitology laboratory. Thin and thick thin blood samples were prepared and stained with Giemsa method and modified knott method. The obtained data were analyzed by SPSS 18 statistical software. The overall prevalence of parasite was 30.3%, seven of 49 shepherd dogs (14/3%) and twenty three of 50 stray dogs (46%) were positive. From 30 positive samples, 14.3% of shepherd dogs and 50% of stray dogs were male, and 44.7% of stray dogs were female. 14% of infected shepherd dogs and 38.5% of infected stray dogs were indigenous, and 16.7% of infected shepherd dogs and 72.7% of infected stray dogs were hybrids. There was no statistically significant relationship between the prevalence of D. immitis with age, gender, breed and usage of anti-parasitic drugs. Due to the relatively high contamination of dogs in the city of Iranshahr with this parasite, veterinarians and public health professionals should be considered necessary and preventive measures in relation to this disease.
Keywords: Dirofilaria immitis; Dirofilariasis; Dog; Iranshahr; Southeast of Iran.