FEATURES OF THE HISTOLOGICAL STRUCTURE THE LIVER OF СARASSIUS GIBELIO BY SAMARA RIVER (DNIPROPETROVSK REGION)

Abstract

One of the most revealing methods of the influence of adverse environmental factors on the body of fish today is the study of structural and functional changes in its tissues. In particular, changes in the histological structure of the hepatopancreas in response to the action of various stress factors can manifest, for example, in the form of fatty dystrophy, tissue destruction, necrosis. These changes can be used as biomarkers and show the sensitivity of the fish body to environmental factors. For the first time it was study the histological structure and pathologies of the tissue structure of the hepatopancreas the prussian carp (Carassius gibelio) of the Samara River of the Dnipropetrovsk region. The generalized research results were obtained during 2019–2021. The research was conducted within Novomoskovskiy district of Dnipropetrovsk region. Three research areas along the water area of the Samara River were chosen for the study, which had a different nature of anthropogenic influence. The object of the study were six-year-old silver crucian carp of both sexes. Determining the age of the fish was carried out on the scales according to the generally accepted method. The hepatopancreas was obtained from freshly caught fish by anatomical dissection. Histological studies were performed in accordance with generally accepted methods. The results of histological studies showed the presence of pathological changes in the structure of the hepatopancreas in fish from all experimental points. In particular we were found such pathologies as vacuolization of single cells, dysplasia of hepatocytes, lipoid degeneration, deformation of liver lobules. Single cases of cystic and pigment neoplasms, hemorrhagic infiltrates, and the presence of acentric nuclei were recorded. Most often, histopathological changes in the structure of hepatopancreas were observed in fish caught near the city of Novomoskovsk. The obtained data on histological changes in the structure of hepatopancreas of fish can be used to identify mechanisms of adaptation to the influence of anthropogenic factors on hydrobionts, and will also provide an opportunity to monitor the condition of a certain population under anthropogenic pressure.