The monograph summarizes the data of own research and studies of Ukrainian and foreign literature about ecological peculiarities of the distribution of ruminant geohelminths and the most frequently encountered zoonosis on the territory of Ukraine. Consistent presentation of the material reveals the nature of the occurrence of invasive disease and its spread. Methods for identifying parasites that contribute to the qualitative differential diagnosis of ruminant geohelminthes invasions are described. The distribution of diseases and eсological factors that contribute to the transmission of zoonosis are analyzed. The data presented are the basis for a scientifically based control measures against invasive diseases