Distinct habitats as a determinant of roe deer <em>Capreolus capreolus</em> L. abomasal nematode compound community

The composition of roe deer <em>Capreolus capreolus</em> abomasal nematode compound community depends on several factors; however, little is known about the impact of habitat and host co−occurrence. Roe deer appears to be the most suitable host species model for conducting studies on formatting the parasitic fauna of wild and domestic ruminants. Therefore, this study was conducted to find out whether the connection between the abundance of a particular roe deer abomasal nematode species and the habitat (i.e. agricultural land, the urban agglomeration, mountains and forests) can be determined. Special emphasis was placed on the mean abundance values which were used in correspondence analysis performed to clarify the observed connection. Based on post−mortem examinations of 75 roe deer overall, 12578 nematodes belonging to eight species (<em>Ostertagia leptospicularis</em>, <em>O. antipini</em>, <em>Spiculopteragia boehmi</em>, <em>S. asymmetrica</em>, <em>Haemonchus contortus</em>, <em>Ashworthius sidemi</em>, <em>Trichostrongylus axei</em>, <em>T. askivali</em>) were collected. The majority of the nematode species were derived from the forest roe deer population co−occurring with red deer <em>Cervus elaphus</em>, fallow deer <em>Dama dama</em> and moose <em>Alces alces</em>, whereas the lowest species diversity was observed in abomasum of roe deer living in the habitat without permanent existence of other cervids (agricultural land). The highest mean intensity of infection was reached by <em>A. sidemi</em> found in roe deer inhabiting forests, while the lowest by <em>T. askivali</em> found in roe deer from mountain habitat. The co−infection of <em>H. contortus</em> and <em>A. sidemi</em> was noted in 11 analysed roe deer. The results suggest that the sympatry favors the exchange of <em>A. sidemi</em> between the representatives of Cervidae. Identification of <em>T. axei</em> in the majority of analyzed habitats indicates that roe deer participate in parasite transmission between wild and domestic ruminants. The results show that the presence of a particular roe deer abomasum nematode species does not only depend on occupied habitat but is also strictly connected with the sympatry.