摘要:In Europe the species of ticks most frequently parasitizing humans is Ixodes ricinus (castor bean tick, sheep tick). The greatest medical significance of this tick is related to its being a vector for bacteria Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum, spotted-fever rickettsias, tick-borne encephalitis virus and protozoa Babesia spp., transmitted to the host usually during feeding.Aim. The aim of the study was to describe the feeding process of the castor bean tick – Ixodes ricinus and to analyze the factors affecting this species’ capacity to transmit pathogens.Material and methods. The study investigated the feeding of Ixodes ricinus adult forms on rabbits at room temperature 20±3°C. The following parameters of the parasitic stage were determined: feeding period, increase of female body mass, feeding efficiency index, and tick yield. Long feeding periods and high aggressiveness of females, as well as large quantities of blood drawn from the host, create favourable conditions for effective transmission of pathogens to the host during feeding.Conclusions. Research on the tick feeding process and factors affecting the parasitic stage is of great importance for the understanding of pathogen transmission, which may contribute to development of effective methods reducing its harmful consequences.