The influence of Trichinella spp. infection on hematological parameters of hens

The purpose of the research is to study dynamics of the peripheral blood cell composition during experimental infection of hens with Trichinella pseudospiralis.Materials and methods. . Two groups were formed according to the principle of analogues, experimental and control, of 10 and 6 laying hens, respectively. The experimental birds were weighed, and the isolate of T. pseudospiralis larvae was administered intragastrically at a dose of 2 sp./g of body weight (4000 thousand larvae per bird). Blood samples were taken from the axillary vein before and at days 4, 7, 11, 14, 18, 28, 35, 43, 53, and 61 after the infection. Hematological parameters (total number of erythrocytes and leukocytes, and hemoglobin concentration) were determined by established laboratory methods with subsequent calculation of the leukogram.Results and discussion. It has been established that trichinellosis in the hens caused by parasitism of non-encapsulated Trichinella spp. species does not affect the number of erythrocytes and hemoglobin in infected birds. Indicators of the Trichinella-associated process are cells in the granulocytic series, eosinophils. The onset of the body's reaction to the infection as expressed by eosinopenia was detected at day 7 after the infection. An increase in the relative content of basophilic and eosinophilic granulocytes was recorded in the hens’ blood from day 18; such parameters reached their maximum values on days 25 and 35, that corresponds to the migratory and muscular stages of the Trichinella-associated process. A relative and absolute quantitative decrease in these groups of cells was subsequently detected in the hens’ blood; however, these values were higher than the control non-infected hens during the entire follow-up (61 days). The dynamics of eosinophils and basophils circulating in the hens’ blood was due to the Trichinella-associated process staging and confirms the predominance of an allergic reaction in the nature of such disease.