SIGNIFICANCE OF TERRESTRIAL MOLLUSKS IN THE FORMATION OF DICROCELIASIS FOCI IN THE FOOTHILL ZONE OF THE REPUBLIC OF NORTH OSSETIA-ALANIA

Abstract

The Republic of North Ossetia Alania remains contaminated by a number of trematode infections including dicroceliasis. The infection rate of cattle is on average 53% in the Republic. Five hundred twenty-six specimens of terrestrial mollusks were collected by the route method in various biocenoses of the foothill zone located at an altitude of 530 – 850 m above sea level. Fourteen species were identified. The dissections revealed that dicroceliasis foci were maintained and function with the involvement of two species of terrestrial mollusks in stock routes and pastures of the studied zone. According to the laboratory studies, infection of the mollusk Helicella derbentina (Kryn.) with the trematode larvae was 5.1%. Five of 98 dissected specimens were infected. The infection rate in Chondrula tridens (Mull.) was 4.6%. During the helminthological study of 87 specimens of this species, dicrocelia larvae were found in 4. According to preliminary data, such species of the studied terrestrial mollusks as Succinea pfeifferi (Rossm.), Cochlicopa lubrica (Műll.), Euomphalia ravergieri (Fer.), Euomphalia selecta (Klika), and Fruticocampylaea narzanensis (Kryn.) identified in stock routes and pastures of the foothill zone do not participate in the development cycle of the trematode Dicrocoelium lanceatum. Further research is required.