Abstract
Examination of the biodiversity of horse strongylid communities was performed on 51 domestic horses from Southern Poland and Western Ukraine by in vivo method. All horses were dewormed with macrocyclic lactone anthelmintics. Strongylids (34,715 specimens) were collected and identified by morphological criteria. In Poland, 25 strongylid species were found. Five cyathostome species dominated in the community. Large strongyles were found in 23.1 % of horses and composed 0.56 % of total strongylid number. General structure of strongylid community was multimodal with dominant, subdominant, background and rare species. In Ukraine, 19 species were found. Five cyathostome species dominated in the community. Strongylinae were found in 17.4 % of horses and composed 0.07% of community. General structures of strongylid community were multimodal or bimodal depends on type of horse keeping conditions. Regularity of anthelmintic treatment was found to be more influential on strongylid community structure than differences in horse-keeping conditions at the both countries.