Problems of compensative fisheries: increasing the adaptive potential of broad whitefish Coregonus nasus (Pallas) in early ontogenesis by weak magnetic fields. 2. Histological analysis

Abstract

In the second part of the article, we performed a cytological and histological analysis of the important functional systems of the control and experimental batches of juvenile broad whitefish as a result of a production experiment at the Sobskiy fish hatchery (settlement Kharp, YaNAO). The experimental batch was processed by the employees of Telos-Siberia LLC using generators of ultra-weak pulsed magnetic fields at the final stages of embryogenesis. We studied the state of internal organs, control and experimental juveniles of this species in the postembryonic period. During the cytological and histological analysis, no pathological changes in the internal organs were revealed. But the treated larvae showed a longer development of the nervous system; in larvae and fry, an intensive course of gameto- and gonadogenesis was noted. A significant increase in the number of primary gonocytes in larvae, larger sex glands and numerous gonocytes in fry has been shown. Also, the experimental fry underwent anatomical and cytological differentiation of the gonads in the direction of the ovaries earlier than in the control. At the end of the rearing period before being released into the Ob for feeding, the number of germ cells in experimental females significantly exceeded the corresponding number in control individuals. The data obtained allow us to conclude that superweak pulsed magnetic fields accelerate the development of the reproductive system, increase the reproductive potential of an individual and do not have a negative effect on the development of somatic systems.