Molecular detection and investigation of the presence of dirofilariosis causative agent in dogs on the territory of Belgrade

Dirofilariosis in dogs is a parasitic disease caused by the strains Dirofilaria immitis and D. Repens. Dirofilaria immitis parasitizes in the right side of the heart and pulmonary artery, causing considerable functional impairment of the heart, while adult forms of D. repens mostly parasitize in subcutaneous tissue causing minor skin damage. In this investigation, during the period from May to November 2015, 60 dogs of different race from the territory of Belgrade were examined. Ater the clinical examination, the blood was sampled for microfilariae detection by Knott test, as well as for molecular detection of the agent. Main clinical signs were: fatigue during exersise, shortness of breath and dry cough, anorexia, rapid heartbeat and skin changes. Microfilariae were detected in 22 dogs (37%) by modified Knott test. By molecular genetic method there was determined the prevalence of D. immitis 42%, and D. repens 22%. In this investigation 7 dogs were negative on Knott test, but by PCR method they showed a positive reaction on the presence of species of the genus Dirofilaria. On the basis of the obtained results, the application of molecular-genetic methods is justified in accurate and reliable species identification of Dirofilaria genus.