Some Features of the Blood Cellular Composition and Histology of Muscles of Female and Male Beaked Redfish (Sebastes mentella)

Materials of the histostructure and clinical parameters of the blood of sexually mature females and males of the beaked redfish (Sebastes mentella) from the pelagial zone of the Irminger Sea (northeastern Atlantic) made it possible for the first time to describe the features of the morphological structure of the body and present the characteristics of blood cells. The diameter of white and red muscle fibers along the body (from head to tail) in females and males of the beaked redfish differs significantly. In addition, females differ from males in the distribution of the fiber density along the body. The morphology and size of erythropoietic cells and leukocytes in beaked females and males are similar to those of other fish species. Nevertheless, erythropoiesis and leukopoiesis of males and females proceed differently. Significant differences in the composition of the somatic muscles of females and males indicate a higher rate of metabolic processes in females. In the leukogram of females, the proportion of mature segmented neutrophils, which are the main microphages with high antigenic activity, is significantly higher than in males. Therefore, females have a higher cellular factor of innate immunity.