Fractional Composition of Blood Serum Proteins of Freshwater Fishes under the Cobalt Ions Impact

The fractional composition of blood serum of crucian carp (<i>Carassius gibelio</i> Bloch.) and pike (<i>Esox lucius</i> L.) under the impact of 2 and 5 maximum permissible concentrations (MPC) of cobalt was studied. Increased concentrations of cobalt ions caused changes in both total content of serum proteins and their fractional composition. Under the impact of 2 and 5 MPC of cobalt ions total protein content in blood serum of crucian carp increased by 18.9 and 24.8%, respectively, whereas in pike it confidently decreased by 15.8% under the influence of 5 MPC. In crucian carp, 5 MPC of cobalt did not cause significant changes of albumin and γ-globulins content, whereas 2 MPC caused decrease of α<sub>1</sub> and α<sub>2</sub> -globulins and increase of β-globulins content. In pike, 2 MPC caused confident increase of albumin and α<sub>2</sub> -globulins content and decrease of the β- and γ-globulins, and5 MPC caused increase of β-globulins and decrease γ-globulins content. Significant increase of the albumin/globulin ratio was noted only in pike blood serum under the impact of 2 MPC of Co<sup>2+</sup> ions. Further studies of the adaptive responses of the blood system of the freshwater fishes are promising for both assessment of their organism health and biomonitoring of hydroecosystems in terms of cobalt intoxication.