**7. Conclusions**

European bison survived to the present times, only thanks to human care and protection. Because Europe, unlike the Americas, was significantly more populated in the Middle Ages, European bison conservation by the Polish kings saved this species from total extinction, as was the case outside the Kingdom of Poland. Successive rulers continued to protect the species, but warfare led to the total depopulation of the last surviving free-living population in the Białowieża Primeval Forest. Thanks to the efforts of scientists and naturalists, the current global population of European bison which was founded by 12 individuals is over 7000. This is undoubtedly a success, but without the supervision of the health of European bison, it would be impossible. European bison, in general opinion, is characterized by a decreased resistance to infections due to their low genetic heterogeneity after passing through the "bottleneck." Except for *Mycobacterium* spp. and foot-and-mouth disease, there are few threats threatening to total depopulation of the species at the moment. However, many European bison seems to be susceptible to many pathogens which may influence their health status and exclude genetically valuable individuals from the breeding. Monitoring of the exposure is essential for the knowledge but also for taking the necessary steps to protect and control. It requires a sampling plan, which allows collection of representative number of specimen necessary for statistical analysis, which is not always feasible since European bison are few and most live in the wild. Therefore, many discussed above studies do not meet any epidemiological assumption and need to be analyzed with caution. Many retrospective studies suggest that European bison may be a reservoir of pathogens; however, the susceptibility to the infection is arguable, since they do not manifest any clinical symptoms (borreliosis, toxoplasmosis). In contrast to high-production animals, it seems not to be highly susceptible to infection, e.g., with pestiviruses and herpesviruses. At the same time, the possible interspecies transmission between domestic ruminants and European bison may be possibly responsible for the high prevalence of respiratory viruses and *Pasteurella multocida* infections in which clinical manifestations are observed frequently postmortally in European bison. Changing environment brings new challenges to European bison protection too, since the entire population may be at risk due to the emerging and re-emerging diseases observed recently such as bluetongue disease and malignant catarrhal fever. Therefore, maintaining the health monitoring of free-living European bison and eliminating all epizootic threats from the environment are crucial. It is also very important to follow the veterinary procedures and appropriate prophylactic measures when moving these animals. In our opinion, "prevent to protect" should stand for active protection, which proved to be the most effective in European bison restitution so far. Restitution breeding is a long and tedious process, often associated with making difficult and unpopular decisions.
