The current situation analysis at the parasite fauna of semi-aquatic carnivores of the weasel family in the central region of the Russian Federation.
Most members of the Mustelidae family living in the Central Non-Black Earth Region of Russia are the objects of sport and commercial hunting. Some of them are bred in fur farms (mink, polecat) and kept at home as decorative animals. The close contact of a person with various members of the family of mustelids, which increase with the development of urbanization processes, makes significant role of mustelids as sources of dangerous invasions for humans and animals (trichinosis, echinococcosis, etc.). We examined 48 ferrets, 107 American minks, 25 European minks, and 11 otters in order to determine the species composition of animal parasites, in the period 2000-2018. They were examined according to methods commonly used in parasitology about muscle tissue, internal organs, and thoracic and abdominal cavity. Animals for research were obtained from hunters from the Central region of the Russian Federation. Studies have shown that ferrets are invased with 8 species of parasites belonging to two classes: Trematoda (3 species) and Nematoda (5 species). The parasitic fauna of the minks was represented by 15 species of worms: Trematoda (2 species), Cestoda (1 species), Nematoda (12 species). The American mink is infested with 14 helminth species and the European mink with 11 species. Otters were infested with 2 classes of parasites: Trematoda (1 species) and Nematoda (1 species). We explain the high contamination of ferrets and minks of E. perfoliatus by the constant presence of animals at the reservoirs where the intermediate owners of helminths (fish) live. Also, a significant proportion in the diet of many species of weasels are tailless amphibians (frogs), which explains the infection of semi-aquatic animals with an unusual species of trematodes Alaria alata (larvae).