Study of changes in the histological structure of the gills of carp and zander living in lake Balkhash

Abstract

The problem of adaptation and reactivity of an organism to various environmental factors is one of the central problems in theoretical and practical biology. At present, the attention of researchers is especially attracted bythe issues of ecological adaptation. Morphological works that shed light on the corresponding structural and functional rearrangements of fish gills in connection with their ecology are still poorly understood. In particular, the issues of comparative morphological assessment of the adaptive responses of gas exchange organs have not been developed. The impact of the enterprises of the metal and mining complex is reflected in the tissues of the organs of fish. Thus, environmental factors, such as the accumulation of heavy metals in water, subject the fish body to a structural and functional rearrangement, thereby changing the normal tissue structure. In this regard, the purpose of the study was to study changes in the histological structures of the gills of carp and zander living in Lake Balkhash. Changes in the tissue structure of the gill arch of fish were in the form of emerging pathologies, the frequency of which was noted using a comparative analysis. For the implementation of this work, a histological, morphometric and statistical study of the tissues of the gills of the studied fish individuals was also carried out. The following pathological processes were observed in the structure of the gills of carp and zander: changes in the shape of secondary lamellae, hyperplasia of the gill epithelium, necrosis and edema of the respiratory epithelium, as well as foci of hemorrhages. The detected changes in the histological structures of fish gills indicate the impact of external environmental factors, one of which, in this article, is the accumulation of heavy metals in water. This study was carried out from a natural ecosystem, thus, literary sources are used to compare the data obtained.