An Anatolian wild sheep (Ovis orientalis anatolica) from a wild ruminant farm near Kirikkale, Turkey, was necropsied. Parasitic nodules were situated beneath the pleura of the caudodorsal lobes of the lungs. First stage larvae of Cystocaulus ocreatus were detected both in bronchial fluid and in lung paraffin sections. Clinical and parasitological examinations of the other animals (4 dwarf goats and 3 wild sheep reared on the same farm) were also performed. First stage larvae of C. ocreatus, and eggs of Nematodirus spp. and Strongyloides spp. were observed in coproscopic examination. Anthelmintic treatment, Rabenzole (R) (rafoxanide and thiabendazole, Topkim), was administered to the animals infected by parasites. At the end of the treatment the combination of rafoxanide and thiabendazole was found to be markedly effective for the treatment of lungworm infection and no parasitic eggs were detected in the faeces of any of the treated animals.