LEUKOCYTE FORMULA OF PERIPHERAL BLOOD IN RODENTS (ORYCTOLAGUS CUNICULUS) WITH CHRONIC OPISTHORCHIASIS

In laboratory studies of the leukocyte blood count in humans with acute opisthorchiasis, pronounced eosinophilia and neutrophilic leukocytosis are noted, also in an experiment in rodents (Oryctolagus cuniculus), when modeling opisthorchiasis invasion, pseudo-eosinophilic leukocytosis and basophilia are noted, without pronounced eosinophilia. In humans with opisthorchiasis, eosinophilia persists in half of the cases during the transition of the disease to a chronic form, while this phenomenon has not been studied in model experiments. The aim of the study was to determine the quantitative changes in white blood cells in opisthorchiasis in the experiment in the late periods of observation. Modeling of opisthorchiasis was carried out on sexually mature male rabbits at the age of 6 months (n = 16). Infection was carried out once orally, introducing 50 metacercariae to each animal. The metacercariae of Opisthorchis felineus were preliminarily isolated under the control of a light microscope from the muscle tissue of Leuciscus idus fish caught in the Tom River (material from the Department of Ichthyology and Hydrobiology of Tomsk State University, Tomsk). The study was started 3 months after infection in the chronic phase of invasion. Ear capillary blood smears of animals were fixed and stained according to Romanovsky-Giemsa and May-Grunwald. The analysis of the results showed the restoration of normal values ​​of individual indicators, with the exception of the number of eosinophils and basophils and all types of pseudo-eosinophils with an increase in the number of monocytes. In general, the leukocyte formula in the chronic phase of opisthorchiasis in animals was characterized by monocytosis, eosinophilia, basophilia, pseudo-eosinophilic leukocytosis and lymphopenia. The number of eosinophils in the observation group compared with the norm and in the group of animals in the acute phase of opisthorchiasis was 3.96 times higher (p <0.05). With an increase in the period of invasion, the number of lymphocytes in animals returns to normal, but does not reach normal values. It can be assumed that the host organism adapts to chronic invasion, and the blood picture takes on a form close to normal. Thus, in case of opisthorchiasis in rabbits after 3 months, changes in the blood formula are noted that are similar to the human body during the chronization of the process, which makes it possible to consider an experimental model adequate for modeling the chronization of invasion. 

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