In the conditions of the veterinary clinic "Beethoven" in Khabarovsk, hematological and biochemical studies of the blood of dogs infected with the nematodes Dirofilaria immitis were carried out. All sick dogs showed changes in the leukocyte formula and deviations of the biochemical parameters of blood serum from the reference values. X-ray images of the animals showed classic signs of Dirofilaria immitis invasion, dilation of large vessels, severe pulmonary hypertension, protrusion of the main pulmonary artery. Echocardiography in animals with the third and fourth stages of the disease showed dilatation of the right heart, expansion of the fibrous ring of the tricuspedal and pulmonary valves, and regurgitation of the third-degree transmitral flow. In the cavity of the right atrium, hyperechoic objects of variable form (dirofilaria) were located. Also, the course of the disease was accompanied by mixed type left ventricular myocardial hypertrophy and impaired left ventricular diastolic function by the type of relaxation impairment. Dirofilariasis of carnivores is caused by nematodes of the genus Dirofilaria: D. immitis, D. repens and D. Ursi. Two species are parasitic in dogs – D. immitis and D. repens. Dirofilaria immitis in the sexually mature stage parasitizes in the right half of the heart and pulmonary artery, and the larval stage, or microfilariae, circulate in the bloodstream. The disease leads to heart failure, endocarditis, ascites and liver cirrhosis, embolism of blood vessels and death of dogs. On the territory of the Russian Federation, the disease is registered everywhere, including the Khabarovsk Territory in the Far East.

Alymova Tatiana M., Gruzdova Olesya V., Kornilova Alyona V., Demkina Olga V.

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