EN
After dissection examination was made of 20 roe deers (in January, May, August and October), from which over 35,000 parasites, localized in subcutaneous tissue, lungs, abdominal cavity and the alimentary tract, were collected. In all 26 parasite species were found, the prevalence and intensity of infection of which are discussed in relation to the seasons of the year. Very high infection of the abomasum by nematodes was found, affecting all the roe deers examined. Compared with other regions of Poland the roe deers in the Borecka Forest are several times more intensively infected by these nematodes, mean intensity of infection being 1671 specimens. Maximum intensity of infection by these parasites occurs in August (3537 specimens) and minimum in January (750). The roe deers in the Borecka Forest have acquired O. antipini + O. lyrataeformis and S. dagestanica from elk, and also O. ostertagi + O. lyrata from European bison. In addition they are also found to share parasites with red deer (O. leptospicularis + O. kolchida and S. boehmi + S. mathevossiani).