CATTLE PARASITE FAUNA STRUCTURE AND EPIZOOTOLOGICAL FEATURES OF HELMINTHIASIS IN THE NORTH CAUCASUS (USING THE EXAMPLE OF THE DAGESTAN REPUBLIC)

The aim of the study is to investigate the structure of the cattle parasite fauna and the epizootological features of helminthiasis in the North Caucasus (using the Republic of Dagestan as an example). Objectives: to study the species composition of helminth fauna in cattle kept on pasture all year round; to study the species composition of helminth fauna and conduct an epizootic analysis of bio- and geohelminthiasis in cattle kept in stationary pasture, distant-pasture and year-round pasture conditions; to study the species composition of helminth fauna and conduct an epizootic analysis of bio- and geohelminthiasis in cattle kept on distant-pasture; to study the dynamics of cattle infestation with biohelminths by season. The study was conducted in 2023–2024 in the Republic of Dagestan. A survey of 200 household farms using various cattle management systems was conducted: stationary pasture, year-round pasture, and distant-pasture. The degree of infestation of animals was assessed using antemortem and postmortem diagnostics, taking into account the study of retrospective data. A total of 1,000 fecal samples were analyzed. To compare the helminthological status of animals kept in different conditions, a complete necropsy was performed on 150 animals. The study included 50 animals each from stationary-pasture, year-round-pasture, and distant-pasture housing systems. Six species of biohelminths and 12 geohelminths were detected in cattle kept on stationary pastures; 27 species of helminths were found in year-round cattle; and 17 common species of biohelminths and geohelminths were found in distant-pasture cattle. During the study, parasites of epizootic significance in animal helminthiasis were identified: D. lanceatum, O. ostertagi, O. circumcincta, T. axei, T. columbriformis, N. spathiger, N. helvetianus, Oes. radiatum, Oes. venulosum, B. trigonocephalum, B. Phlebototomum, H. placei, and demonstrated a high level of infection, with an extensiveness of invasion (EI) from 50.0 to 68.0 % and an intensity of invasion (II) varying from 116.7 ± 20.3 to 191.2 ± 28.5 individuals per animal.