Occurrence of dirofilaria immitis (Nematoda, onchocercidae) in red foxes (vulpes vulpes) from the suburbs of Kharkiv (Ukraine)

Abstract

Dirofi lariasis of animals and humans is a disease caused by nematodes of the genus Dirofi laria (Railliet et Henry, 1911). Th e role of wild predators, particularly the red fox (Vulpes vulpes) (Linnaeus, 1758) in the distribution of pathogen of the genus Dirofi laria in the world remains unclear. We studied the occurrence of Dirofi laria immitis (Leidy, 1856) in a population of the red fox. Twenty-seven foxes were examined during the winter hunting season of 2019–2020 in Dergachi district, Kharkiv region of Ukraine. All 27 examined foxes were older than 1.5–2 years old, 5 of them (18.5 %) were 4–5 years old. Dirofi laria immitis was found in 22.2 % of foxes. Th e intensity of infection ranged from 2 to 4 specimens of nematodes per host. In four foxes (66.7 % of infected hosts), the same number of male and female nematodes was detected, while two foxes (33.3 %) had each 1 male and 2 females of D. immitis. Th e length of D. immitis males (7 specimens) was 13.96 ± 0.29 cm and the length of females (9 specimens) was 19.58 ± 0.55 cm. Prevalence of infection of foxes with D. immitis presumably depends on their habitat and the presence of mosquitos (vectors of the nematode) in these areas.