A Comparative Study of the Leukocyte Formula of the Peripheral Blood, Head Kidney and Spleen of the Bream Abramis brama (Cyprinidae) in the Middle Volga Reservoirs

A comparative study of the leukocyte formula of peripheral blood, the head section of the kidney and spleen of the bream Abramis brama, inhabiting the reservoirs of the Middle Volga (Kuibyshev, Cheboksary and Gorky), was carried out. In the studied fish, a predominance of lymphocytes and a low content of neutrophils were recorded in the peripheral blood and spleen. In the head kidney of the breams from the Kuibyshev Reservoir, a significantly high level of blast forms of cells and a low level of neutrophils were noted, and in individuals from the Gorky Reservoir, a low content of monocytes and the absence of eosinophils were noted compared to fish from other reservoirs.