Histomorphological Changes in Gill Epithelium of Kaluga Acipenser dauricus and Amur Sturgeon Acipenser schrenckii (Acipenseridae) from the Amur Estuary

摘要

Fish gills are a polyfunctional organ; in its epithelium, several important interconnected processes— respiration and osmoregulation, in the first place—are exercised (Matei, 1990). Gills contact with the environment and are highly sensitive to itsstate. In the gill epithelium that serves as a tissue barrier on the way of delivery of toxic compounds to the fish body, adaptive processes on organ, tissue, and cellular levels take place (Matei, 1990). Studies that were performed on different fish species both caught in ecologically unsuccessful areas and under conditions of an experiment at exposure with organic and inorganic pollutants showed a negative impact of pollution on the state of gill epithelium (Solangi and Overstreet, 1982; Mallat, 1985;Romanov et al., 1998; Kryuchkov et al., 2000; Syasina et al., 2000; Syasina and Sokolovskii, 2001; Flores-Lopes and Thomaz, 2011; Adeogun, 2012).In the Amur basin and Amur liman, two representatives of the family Acipenseridae dwell—kaluga Acipenser dauricus (=Huso dauricus) and Amur sturgeon A. schrenckii. In both species, different histomorpho-logical disturbances of the reproductive system and muscular tissue presumably determined by pollution of the Amur basin were recorded (Koshelev et al., 2009; Koshelev and Evteshina, 2011). Histopatholog-ical study of the gill epithelium particularly sensitive to pollution of the aquatic environment wasnot previously performed in Acipenseridae of the Amur.The purpose of the study was to estimate the state of the gill epithelium of kaluga and Amur sturgeon using morphological and histopathological indices.