THE STUDY OF THE MUSCULAR SYSTEM OF THE TREMATODE DICROCOELIUM LANCEATUM

This paper presents the results of a study of the muscular system of the trematode D. lanceatum, the causative agent of dicrocoeliosis, a widespread parasitic disease of the grass-feeding ruminants. As a result of the used fluorophore-conjugated phalloidin, data were obtained on the organized muscles of the body wall, attachment organs, and digestive, reproductive and excretory systems of D. lanceatum. The body wall musculature is represented by three layers of muscle fibers: circular, longitudinal and diagonal. The character of the muscle fiber location is different in the anterior, middle and posterior parts of the body. The paper describes several types of muscle fibers found in the oral and ventral suckers, and digestive, reproductive and excretory systems of the parasite. An analysis of the data obtained and available in the literature showed the presence, along with common features, of differences in the organization of the muscular system of various trematode species. The results obtained expand and deepen the understanding of the trematode morphology, the organization of their muscular system, and make it possible to detect similar and different features in the structure of the muscular system of organs and tissues of species of various taxonomic groups of trematodes. In addition, the study of the muscular system of trematodes may be important in identifying new additional diagnostic criteria necessary for solving a number of taxonomic tasks.