Mollusks (Gastropoda) as intermediate hosts of cattles' trematodes (Trematoda) in conditions of Dnipro basin's small ponds (northern Ukraine).
The article presents the data on distribution and defeat of gastropod mollusks by parasitic trematodes in biotopes of small reservoirs (rivers, lakes and swamps) of the Dnipro basin of northern regions of Ukraine. During the 2016-2017 years, at the following areas were collected and identified: Lymnaea (L.) stagnalis (Linnaeus, 1758); L. truncatula (Müller, 1774); Planorbis (P.) corneus (Linnaeus, 1758); P. planorbis (Linnaeus, 1758); Viviparus contectus (Millet, 1813); Valvata piscinalis (Müller, 1774) and Succinea pfeifferi (Rossmässler, 1834). The microscopic study of the mollusks' liver allowed us to detect the presence of pathogens of cattle trematodoses inside a certain number of the snails-Fasciola hepatica (Linnaeus, 1758) and Paramphistomum sp. (Fischoeder, 1901). At biotopes of small rivers, 8.3% of mollusks L. truncatula species, 23.5% of L. stagnalis and 5.7% of P. corneus were affected. At lakes and swamps, the number of affected L. truncatula was 36.3%, and L. stagnalis-13.7%. It was determined the defeat of ruminants with fasciolosis and paramfistomatoses in designated regions. It testifies to the formation of sustainable natural foci of these invasions.