Dirofilaria immitis infection in carnivores from Bulgaria: 2012–2013 update

Abstract

Helminthological necropsies of 489 carnivores (325 golden jackals, 115 red foxes, 4 martens, 3 wolves, 27 domestic dogs and 15 cats) from Bulgaria were carried out in 2012–2013 aiming to establish infection with Dirofilaria immitis (Nematoda: Onchocercidae). The infection was found in the golden jackals, red foxes and domestic dogs. Adult worms were located in the heart (55.24%) or both in the heart and pulmonary arteries of the hosts (27.97%). Often in the place of localisation of the helminths macroscopic lesions as obturation of pulmonary arteries, thickness and granulation of the inner surface of pulmonary arteries, damaged atrioventricular valves were observed. The prevalence of infection was 37.54%, 25.22% and 33.33% in the golden jackals, red foxes and domestic dogs respectively. The infection intensity in the jackals varied between 1 and 19 specimens per animal (mean 4.1), in the foxes it was between 1 and 15 specimens (mean 4.79) and in the dogs – between 1 and 34 specimens (mean 14.43). Comparison of our data with those from literature showed a trend towards increased spread of infection in Bulgaria and South Europe in recent years. Morphometric description of D. immitis in materials from golden jackals, red foxes and domestic dogs was performed too. This is the first report in materials from golden jackals and red foxes.