ON IMMUNOPHYSIOLOGICAL STATUS OF THE BLACK SEA TURBOT <i>SCOPHTHALMUS MAEOTICUS MAEOTICUS </i>AT DIFFERENT REPRODUCTIVE STAGES
Results of the long-term studies of the nonspecific immunity factors in the turbot breeders from th e north-eastern part of the Black Sea during the pre-spawn, spawning and post-spawn periods are presented. Data on leukocyte composition, lysozyme, immunoglobulins and immune complexes of the blood serum were obtained. It is shown that, in natural conditions, the activity level of the cellular and humoral components of immunity is determined by annual rhythms associated with maturation of the sexual products and the temperature conditions of the medium. Turbot peripheral blood leukocytes are mainly represented by lymphocytes and neutrophils, the latter ones showing predominance of stab neutrophils in the composition. During the spawning period, the fraction of neutrophils in the turbot white blood decreases, as well as the fraction of stab cell forms in th e neutrophil composition (in females). Sex differences in the state of humoral immunity are found in breeders dur ing the spawning period, and they are obvious due to certain indicators. Before spawning, immunophysiological status of both females and males is normally achieved by high concentrations of lysozyme and immunoglobulins. In the active phase of the cycle, a decrease in the content of lysozyme and immunoglobulins and an increase in the content of immune complexes were recorded in the blood serum of females. In the turbot males, the completion of its reproduction cycle is characterized by an increase in lysozyme, a decrease in immunoglobulins and by stable values of immune complexes.