Some cytometric and biochemical parameters of the blood of Prussian carp (Carassius gibelio Bloch, 1782) of the Samara river, Dnepropetrovsk region

Purpose. To determine the presence of functional changes in the cytometric and biochemical parameters of the blood of Prussian carp of the Samara River under conditions of human impact. Methodology. The object of the study was age-6 Prussian carp (Carassius gibelio (Bloch, 1782)) of both sexes. The material for the study was collected with the use of gill nets during scientific fishing in the summer-autumn period in 2019. Blood was collected from the caudal vein. Morphological studies of erythrocytes were carried out on blood smears, which were stained according to Romanovsky-Giemsa. Blood smears were studied at 40X magnification using a photomicrograph with a Sciencelab T500 5.17 M digital camera. On the preparations, 150 visual fields were examined. Biochemical studies were carried out on automatic analyzers OLYMPUS AU400 and AU480 from BeckmanCoulter (USA), using BeckmanCoulter reagents. Statistical processing of the data obtained was carried out according to generally accepted methods in MS Excel 2010. Findings. Age-6 Prussian carp (Carassius gibelio (Bloch, 1782)) of the Samara river, under conditions of anthropogenic impact, were found to have an increase in their glucose content (28.5 - 37.4 mmol/l), as well as an increase in ALT (46.5 - 52.8 U/L) and AST (85.1 - 100.5 U/L) activities in blood that may indicate the formation of certain protective mechanisms for adaptation to the effects of harmful environmental factors. These parameters were highest in specimens caught near Novomoskovsk. Cytometric analysis showed a statistically significant increase in the nuclear weight, the size of erythrocytes and an increase in the nuclear-plasma ratio of red blood cells of fish caught near the village Khashchove and Novomoskovsk. It can indicate the inhibition of the functional activity of erythrocytes. The value of the albumin-globulin coefficient (0.6) and the de Ritis coefficient (1.8 - 1.9) of Prussian carp at all experimental points of the Samara river indicates the beginning of the formation of certain pathological processes in their liver and heart. Originality. The study of cytometric and biochemical parameters of the blood of Prussian carp of the Samara river of the Dnepropetrovsk region subjected to the significant human impact was performed for the first time Practical value. The data obtained can be used to conduct hydroecological monitoring of natural water bodies and to determine the degree of the effect of various anthropogenic factors on the health and productivity of commercial freshwater fish species.