Oxidative processes in the immunocompetent organs of pink salmon Oncorhynchus gorbuscha and chum salmon Oncorhynchus keta (Salmonidae) during the marine period

Abstract

The influence of various factors on the fish body is reflected in changes in metabolic processes, including an imbalance of redox processes. The study of the level of oxidative processes and antioxidant protection in the tissues of aquatic organisms is often used in ecological and ecologicaltoxicological studies to assess the environmental conditions. Obtaining such data when conducting comprehensive ichthyological studies makes it possible to assess the features of adaptation to various habitat conditions, as well as the health status of fish. Mature pink salmon Onchorhynchus gorbuscha and chum salmon O. keta were caught in the summer of 2018 in the open waters of the northwestern Pacific Ocean (east of the Kuril Ridge) using a mid-water trawl during a trawl survey. Immediately after catching, liver, kidney and spleen samples were taken from the fish. Test tubes with organ tissue samples were frozen at –20 °С. Homogenates were prepared from thawed organ samples under laboratory conditions. The level of lipid peroxidation products and antioxidant activity was evaluated. As a result, intertissue and interspecific similarities and differences in the studied parameters of pink salmon and chum salmon during the marine period of life were established. The detected differences in indicators are presumably related to the structural and functional organization of the tissues and organs studied, as well as species characteristics. The results can be used to monitor population health and compare with closely related species.