Features of the microscopic structure of the intestinal wall in females of the ixodic tick of the genus Dermacentor during the feeding period

Ixodic ticks of the genus Dermacentor are parasitomorphic ticks that are carriers of a number of dangerous zooanthropozonoses, have a wide distribution. The intestine of an adult contains several types of cells: digesting, secretory, reserve and yolk cells. Digestive cells of types 1 and 2 are involved in the process of intracellular digestion and are the main components of the wall of the middle intestine. After insemination, yolk cells begin to form in the intestine, regulating the development of oocytes. The research was carried out on the basis of the Department of Parasitology and Veterinary and Sanitary Examination, Anatomy and Pathanatomy named after Prof. S. N. Nikolsky and at the Scientific Diagnostic and Therapeutic Veterinary Center of the Stavropol State Agrarian University, as well as on the basis of veterinary clinics of IP Zaichenko "Veterinary Center named after Pirogova". The object of the study was ixode mites, the material for the study was the digestive system of females, in particular the middle part of the intestine. Macroscopic examination of the nourished females of the Dermacentor tick helped to reveal that the intestine is an unpaired tubular organ divided into three sections: the esophagus, the sac-like meatus and the small intestine. With the arrival of blood, the intestine expands, as a result of which reserve cells begin to grow and differentiate into primary digestive ones. By the time egg laying begins, digestive cells of type I degenerate and are replaced by digestive cells of type II, differentiated from reserve cells. In nourished females, with an active process of vitellogenesis, the presence of specialized yolk cells is noted. Thus, with the beginning of the feeding period in ixodic mites, an increase in the intestine occurs due to the asynchronous development of digestive cells of type I and II. During digestion, secretory cells are focally exfoliated into the intestinal cavity filled with the host's blood, which characterizes the acceleration of the process of erythrocyte hemolysis. In the final phase of digestion, and the beginning of the vitellogenesis process, yolk cells are formed that regulate the development of oocytes.

1. Zdeněk Franta, Helena Frantová, Jitka Konvičková, Martin Horn, Daniel Sojka, Michael Mareš, and Petr Kopáčekcorresponding. Dynamics of digestive proteolytic system during blood feeding of the hard tick Ixodes ricinus. Parasit Vectors. 2010; 3: 119.

2. Belova, L. M. Ectoparasitoses of cattle in the farms of the Leningrad region / L. M. Belova, A. N. Tokarev // Izvestiya KSTU. Founders: Kaliningrad State Technical University. 2008:13:29-32 URL: https://elibrary.ru/item.asp?id=16689829

3. Pozharova, N. N. Pyroplasmosis of dogs (epizootic situation, some aspects of pathogenesis, treatment and prevention): autoref. dis. ... candidate of Vet. sciences / Pozharova N. N. – Stavropol, 2005:23 URL: https://elibrary.ru/item.asp?id=16067589

4. Tokhov, Yu. M. Phenology of ixodic ticks of the genus Dermacentor in the central Caucasus / Yu. M. Torkhov, S. N. Lutsuk, Yu. V. Dyachenko // Parasitology. 2013:6:437-447. URL: https://elibrary.ru/item.asp?id=20920355

5. Débora Caperucci 1, Maria Izabel Camargo Mathias, Gervásio Henrique Bechara. Histopathology and ultrastructure features of the midgut of adult females of the tick Amblyomma cajennense Fabricius, 1787 (Acari: Ixodidae) in various feeding stages and submitted to three infestations. Ultrastruct Pathol 2009:33(6):249-59.

6. Trukhachev, V. I. Distribution and ecological characteristics of hyalomma ixodid ticks in the ecosystems of the Stavropol region / V. I. Trukhachev, Yu. M. Tokhov, S. N. Lutsuk, A. A. Dylev, V. P. Tolokonnikov, Yu. V. Dyachenko // South of Russia ecology development. January, 2016:11(2):59-69. URL: https://elibrary.ru/item.asp?id=26342875

7. M. F. B. Ribeiro and J. D. Lima. Morphology and development of Anaplasma marginale in midgut of engorged female ticks of Boophilus microplus. Veterinary Parasitology. Volume 61, Issues 1–2, January 1996, Pages 31-39.

8. Débora Caperucci, Gervásio Henrique Bechara, Maria Izabel Camargo Mathias. Ultrastructure features of the midgut of the female adult Amblyomma cajennense ticks Fabricius, 1787 (Acari: Ixodidae) in several feeding stages and subjected to three infestations. Micron 2010:41(7):710-21.

9. R. I. S. Agbede and D. H. Kemp. Ultrastructure of secretory cells in the gut of the cattle-tick Boophilus microplus. Int J Parasitol 1987:17(6):1089-98.

10. Patrícia Rosa de Oliveira, Izabela Braggião Calligaris, Gervásio Henrique Bechara, Maria Izabel Camargo Mathias. Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) nymphs: An ultrastructural study of the integument and midgut. Ticks and Tick-borne Diseases, Volume 5, Issue 6:2014:834-840.

11. Patrícia Rosa de Oliveira, Luis Adriano Anholeto, Gerváso Henrique Bechara, Maria Izabel Camargo Mathias. Dinotefuraninduced morphophysiological changes in semi-engorged females Rhipicephalus sanguineus Latreille, 1806 (Acari: Ixodidae) ticks: Ultra-structural evaluation. Acta Tropica. February 2017:166:139-154.

12. Gavrilova, N. A. Features of morphology of Chorioptes mites parasitizing cattle in the conditions of the North-West of Russia / N. A. Gavrilova, L. M. Belova, M. S. Petrova, O. A. Loginova // Modern problems of general and private parasitology. Materials of the II International Parasitological Forum. St. Petersburg State Academy of Veterinary Medicine; Zoological Institute of the Russian Academy of Sciences. 2017:64-68. URL: https://elibrary.ru/item.asp?id=32246500

13. Loginova, O. A. On the issue of reproduction of ixodic ticks / O. A. Loginova, L. M. Belova, N. A. Gavrilova, M. S. Petrova, Yu. E. Kuznetsov, V. A. Shiryaeva // Modern problems of general and private parasitology. Materials of the II International Parasitological Forum. St. Petersburg State Academy of Veterinary Medicine; Zoological Institute of the Russian Academy of Sciences. 2017:173-176. URL: https://elibrary.ru/item.asp?id=32294638

14. Proskurin, D. A. Development of oocytes of the ixodic tick of the genus Dermacentor / D. A. Proskurin, O. V. Dilekova // Veterinary pathology. 2023:38-45. URL: https://elibrary.ru/item.asp?id=50739164