Episotological characteristics of dog dirofilariasis in the city of Kharkiv

Abstract

Dirofilariasis is a disease caused by nematodes of the genus Dirofilaria, among which the most common
species are D. immitis and D. repens. All over the world, these pathogens are registered among dogs, cats
and humans. Despite significant advances in the field of dirofilariasis, the incidence of canine and severe
infestations due to D. immitis parasitism continues to increase. The purpose of the research was to conduct
monitoring studies of epizootological features of dirofilariasis in dogs in the city of Kharkiv. It was found
that the spread of this infestation among the population of domestic dogs depends on many factors, such as
the season, the way the animals are kept, age and breed characteristics. It was established that the average
infestation of dogs with the causative agent of dirofilariasis in the city of Kharkiv according to the results of
hemolarvoscopic and immunological studies is 28.30 %. Indicators of the intensity of invasion by
microfilaries ranged from 8 to 218 larvae per cm3 of blood. The age dynamics of dirofilariasis is
characterized by maximum damage in dogs aged 5–8 years, where the extent of infestation reaches 41.26 %.
The least infested were young dogs under the age of two (13.95 %). It was found that the most susceptible to
dirofilaries are Rottweiler dogs (51.52 % infestation extent), Caucasian Shepherd Dog (47.83 %), German
Shepherd Dog (41.51 %), Labrador Retriever (40.54 %), Alaskan Malamute (30 %); half-breeds (37.74 %)
and purebred dogs (32.56 %). Seasonal fluctuations are characterized by the peak of invasion in the springsummer
period of the year, where the extent of invasion varied from 28.65 to 39.27 %. Dirofilariasis occurs
in 74.18 % of infected dogs in the form of associations of dirofilaries and nematodes – trichurises, toxocares,
dipylidies, uncinaries, as well as the simplest organisms – cystoisospores. A total of 14 types of mixinvasions
have been established. Selected associations for dirofilariasis consist of two (40.11 %), three (24.73 %), four
(7.69 %) and five (1.65 %) causative agents of invasions. The obtained results of monitoring studies on the
epizootological features of dirofilariasis in dogs make it possible to facilitate the diagnosis of this
infestation, and also, taking into account the established mixinvasions, to effectively carry out treatment and
preventive measures.