Bulletin "Veterinary biotechnology"

Veterynarna biotekhnolohiia– Veterinary biotechnology, 2023, 42, 15-22 [in Ukrainian]. https://doi.org/10.31073/vet_biotech42-02

YEVSTAFIEVA V.1,2, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., MELNYCHUK V.1,2, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., PRYKHODKO YU.2, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., KRYVORUCHENKO D.1, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

1 Poltava State Agrarian University
2 Institute of Veterinary Medicine of the NAAS



Introduction. Due to its impact on the health and welfare of companion animals, dirofilariasis is of great veterinary and economic importance in many countries around the world. In dogs, the invasion is caused by young and adult nematodes, which lead to cardiopulmonary pathology, as well as microfilaries circulating in the bloodstream of animals. Most scientists prove the need to identify D. immitis using the definition of the main and additional morphological structures in both female and male parasites.

The goal of the work was to establish the effectiveness of the proposed and commonly known methods of identification of Dirofilaria immitis nematodes isolated from dogs.

Materials and methods. The work was performed on the basis of the Laboratory of Parasitology of the Poltava State Agrarian University. In order to establish the effectiveness of the dirofilaries identification methods, the preparation of D. immitis nematodes was carried out using three different methods: Lugol’s solution; lactophenol; 1% alcohol solution of diamond green. The degree of visibility of the morphological structures of the nematode body is conventionally divided into: weak, medium, high.

Results of research and discussion. The conducted parasitological studies established the high efficiency of the proposed method of staining nematodes D. immitis, which allows obtaining a high degree of staining of their morphological structures. The method with the use of Lugol’s solution as a dye exceeded the degree of visibility of nematodes under microscopic examination compared to known methods with the use of a 1 % alcohol solution of diamond green and without the addition of a dye. The proposed method led to a high degree of visibility of 6 out of 8 morphological indicators in males and all investigated indicators in female dirofilaries.

Conclusions and prospects for further research:

1. The method of identification of D. immitis with the use of Lugol’s solution as a dye exceeded the efficiency of the well-known methods of illumination and staining of nematodes.

2. The proposed method of staining nematodes Dirofilaria immitis provides a high degree of visibility of the cuticle of the head end, the esophagus, the section of the passage of the esophagus into the intestine, in males – the long spicule, tail papillae, ornamentation of the cuticle in the tail area, in females – the nerve ring, the vulva and uterine loops.

The results obtained by us regarding the application and efficiency of the proposed method of staining nematodes D. immitis will be used in the following tests to improve the efficiency of methods of identification of nematodes of the species Dirofilaria repens.

Keywords: dirofilariasis, dogs, Dirofilaria immitis, nematodes, identification, efficiency.


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