Age and seasonal changes of morpho-physiological state of cyprinids reared by ranching technology in conditions of the southern Ukraine

Purpose. To examine the dynamics of hematological parameters of cyprinids during winter and to determine certain relationships of these or other internal parameters of the experimental groups of the young-of-the-year and yearlings. Methodology. Studies are based on experimental and laboratory methods adopted in the fishery, physiological and statistical studies. Findings. The obtained data of the physiological state of fish after wintering indicate on the reduced content of total blood protein; high number of red blood cells from 1.7 to 2.4 mil/ml in bighead carp and grass carp, high erythropoiesis (8.0–25.0%) of red blood cells; reduction in the content of white blood cells with an increased share of neutrophil granulocyte in leukocyte formula. The biochemical analysis of blood serum showed a typical reduction in total blood protein and reduction in glucose within 25.0–53.1%. There was a pronounced reduction in triglycerides and cholesterol by 24.7–59.5%. Eosinophils, basophils, foam cells and blasts occur sporadically. The correlation analysis showed a significant positive relationship between blood physiological indices and mean weight as well as condition factor in all studied carp species. Originality. The analysis of the hematological parameters of blood parameters in relation to wintering of the young-of-the-year common carp, silver carp, bighead carp, and grass carp reared by fish ranching technology was carried out for the first time. It was found that changes in hematological parameters of carp yearlings indicated on certain changes in the physiological state of fish seeds and could be considered as a specific signal for the development of appropriate preventive measures and optimization of the technological parameters when organizing the process of age-2 fish rearing. Practical value. These data can be used as a component of quality indication and general physiological condition of fish seeds.