Hematological parameters of dogs for parasitism Dirofilaria immitis

Keywords: dogs, dirofilariasis, Dirofilaria immitis, hematological indicators intensity of invasion, microfilariae


The relationship between helminths and the host is built on a subtle molecular biological basis. Their pathogenic effect is characterized by the mechanical, toxic, inoculating effect on the host organism and the state of reactivity of his organism, immunological and allergic reorganization. It has been proved that helminths of the species Dirofilaria immitis are the most pathogenic nematodes of this genus because the localization of the imaginal stage of the parasite causes more complex pathogenesis of the invasion. The study aimed to establish changes in hematological parameters of dogs infected with D. immitis, considering the intensity of microfilariasis invasion. Studies have shown that the intensity of the invasion of up to 20 larvae/cm3 in the blood of dogs, significant changes in the number of erythrocytes, leukocytes, platelets, hemoglobin, and hematocrit and ESR were not found. The intensity of the invasion of 20–40 larvae/cm3 in infected dogs in the blood decreases the number of erythrocytes by 11.92 % (P < 0.05), the hemoglobin content by 16.33 % (P < 0.05), the hematocrit by 12.70% (P < 0.05) and the number of leukocytes increases by 15.17 % (P < 0.05). Indicators of the intensity of invasion of 40–60 larvae/cm3 in infected dogs showed more significant changes in the blood, which are characterized by a decrease in the number of erythrocytes by 25.54 % (P < 0.001), platelets by 34.03 % (P < 0.01), hemoglobin content by 30.86 % (P < 0.001), hematocrit by 20.56 % (P < 0.001) and an increase in the number of leukocytes by 32.75 % (P < 0.001) and ESR by 1.84 times 0.001). At indicators of the intensity of invasion of more than 60 larvae/cm3, in dogs significant (P < 0.001) decrease in the number of erythrocytes by 47.21 %, thrombocytes by 42.84 %, the content of hemoglobin by 42.27 %, the indicator of hematocrit by 41.57 % and an increase in the number of leukocytes by 44.98 % and ESR by 2.51 times. In the leukoform of dogs with increasing rates of microfilariae invasion, the number of eosinophils gradually increases to 62.38 % (P < 0.001), rod-shaped neutrophils to 27.48 % (P < 0.05), monocytes to 23.21 % (P < 0.01) and the number of lymphocytes is reduced to 45.45 % (P < 0.001). The data obtained indicate the importance of determining these indicators for heartworm disease, which complements the picture of clinical examination of animals and will allow more effective treatment of dogs in this invasion.


Ali, N. M., Behnke, J. M., & Manger, B. R. (1985). The pattern of peripheral blood leucocyte changes in mice infected with Nematospiroides dubius. Journal of Helminthology, 59(1), 83–93. https://doi.org/10.1017/s0022149x00034532

Bonawandt, K. A., Berg, J. M., Joseph, R. J., & Stefanacci, J. D. (2017). Intradural dirofilariasis in a dog with chronic cervical pain. Journal of the American Animal Hospital Association, 53(1), 59–63. https://doi.org/10.5326/JAAHA-MS-6450

Boreham, P. F., & Atwell, R. B. (1983). Adverse drug reactions in the treatment of filarial parasites: haematological, biochemical, immunological and pharmacological changes in Dirofilaria immitis infected dogs treated with diethylcarbamazine. International Journal for Parasitology, 13(6), 547–556. https://doi.org/10.1016/s0020-7519(83)80026-5

Dantas-Torres, F., & Otranto, D. (2013). Dirofilariosis in the Americas: a more virulent Dirofilaria immitis? Parasites & Vectors, 6(1), 288. https://doi.org/10.1186/1756-3305-6-288

Donahoe, J. M., Kneller, S. K., & Lewis, R. E. (1976). Hematologic and radiographic changes in cats after inoculation with infective larvae of Dirofilaria immitis. Journal of the American Veterinary Medical Association, 168(5), 413–417. https://pubmed.ncbi.nlm.nih.gov/130366

Genchi, C., & Kramer, L. H. (2020). The prevalence of Dirofilaria immitis and D. repens in the Old World. Veterinary Parasitology, 280, 108995. https://doi.org/10.1016/j.vetpar.2019.108995

Genchi, M., Rinaldi, L., Venco, L., Cringoli, G., Vismarra, A., & Kramer, L. (2019). Dirofilaria immitis and D. repens in dog and cat: A questionnaire study in Italy. Veterinary Parasitology, 267, 26–31. https://doi.org/10.1016/j.vetpar.2019.01.014

Goggin, J. M., Biller, D. S., Rost, C. M., DeBey, B. M., & Ludlow, C. L. (1997). Ultrasonographic identification of Dirofilaria immitis in the aorta and liver of a dog. Journal of the American Veterinary Medical Association, 210(11), 1635–1637. https://pubmed.ncbi.nlm.nih.gov/9170093

Harvey, J. W., Henderson, C. W., French, T. W., & Meyer, D. J. (1982). Myeloproliferative disease with megakaryocytic predominance in a dog with occult dirofilariasis. Veterinary Clinical Pathology, 11(1), 5–11. https://doi.org/10.1111/j.1939-165x.1982.tb00811.x

Hoch, H., & Strickland, K. (2008). Canine and feline dirofilariasis: life cycle, pathophysiology, and diagnosis. Compendium, 30(3), 133–141. https://pubmed.ncbi.nlm.nih.gov/18409140

Jiménez-Penago, G., Hernández-Mendo, O., González-Garduño, R., Torres-Hernández, G., Torres-Chablé, O. M., & Maldonado-Simán, E. (2021). Mean corpuscular haemoglobin concentration as haematological marker to detect changes in red blood cells in sheep infected with Haemonchus contortus. Veterinary Research Communications, 45(4), 189–197. https://doi.org/10.1007/s11259-021-09800-8

Levchenko, V. I., Sokoliuk, V. M., Bezukh, V. M., Tyshkivskyi, M. Ia., Harkavyi, V. O., Nadtochii, V. P., Nadtochii, V. M., Moskalenko, V. P., Kostiuk, M. M., Shchurevych, H. O., Bohatko, L. M., Sakhniuk, V. V., Holovakha, V. I., Chub, O. V., Slivinska, L. H., & Abdullaiev, Sh. M. (2002). Doslidzhennia krovi tvaryn ta klinichna interpretatsiia otrymanykh rezultativ. Metodychni Rekomendatsii. Bila Tserkva (in Ukrainian).

Maerz, I. (2020). Clinical and diagnostic imaging findings in 37 rescued dogs with heartworm disease in Germany. Veterinary Parasitology, 283, 109156. https://doi.org/10.1016/j.vetpar.2020.109156

Niwetpathomwat, A., Kaewthamasorn, M., Tiawsirisup, S., Techangamsuwan, S., & Suvarnvibhaja, S. (2007). A retrospective study of the clinical hematology and the serum biochemistry tests made on canine dirofilariasis cases in an animal hospital population in Bangkok, Thailand. Research in Veterinary Science, 82(3), 364–369. https://doi.org/10.1016/j.rvsc.2006.09.002

Romano, A. E., Saunders, A. B., Gordon, S. G., & Wesselowski, S. (2021). Intracardiac heartworms in dogs: Clinical and echocardiographic characteristics in 72 cases (2010–2019). Journal of Veterinary Internal Medicine, 35(1), 88–97. https://doi.org/10.1111/jvim.15985

Sevimli, F. K., Kozan, E., Bülbül, A., Birdane, F. M., Köse, M., & Sevimli, A. (2007). Dirofilaria immitis infection in dogs: unusually located and unusual findings. Parasitology Research, 101(6), 1487–1494. https://doi.org/10.1007/s00436-007-0665-x

Still, J., & Konrád, J. (1985). The effect of acupuncture on hematologic and biochemical values in dogs with endoparasitic infections. Veterinarni Medicina, 30(11), 687–698. https://pubmed.ncbi.nlm.nih.gov/3934836

Vlislo, V. V. (2012). Laboratorni metody doslidzhen u biolohii, tvarynnytstvi ta veterynarniy medytsyni. Spolom, Lviv (in Ukrainian).

Younes, L., Barré-Cardi, H., Bedjaoui, S., Ayhan, N., Varloud, M., Mediannikov, O., Otranto, D., & Davoust, B. (2021). Dirofilaria immitis and Dirofilaria repens in mosquitoes from Corsica Island, France. Parasites & Vectors, 14(1), 427. https://doi.org/10.1186/s13071-021-04931-y

How to Cite
Kryvoruchenko , D. (2022). Hematological parameters of dogs for parasitism Dirofilaria immitis. Ukrainian Journal of Veterinary and Agricultural Sciences, 5(1), 36-41. https://doi.org/10.32718/ujvas5-1.06