The ways of circulation of trematodes of fish in inland water bodies of Azerbaijan

Abstract

In 2007–2016 in different water bodies of Azerbaijan by the method of full helminthological dissection 4084 fish of 58 species and subspecies were investigated, 81 species of trematodes of 5 orders and 20 families were found. Of these, 44 species complete their development in fish, for 37 species fish are the second intermediate host. 12 circulation ways in nature were defined, of them the way / – environment – gastropod (asexual reproduction) – external environment – fish – bird (sexual reproduction) – / is used by 33 species. The other ways are used by from one to seven species of trematodes. 28 modes of change of the environment were defined in the circulation ways, of them those, which include gastropods and fish-eating birds are used most frequently. Water bodies which are relatively rich in ecological niches, have a greater variety of life cycles of trematodes. 22 species of trematodes are pathogens of fish, 4 species are dangerous to human. Cercariae of trematodes that use fish as the second intermediate host, can penetrate human skin and cause dermatitis.