The prevalence and control of gastrointestinal nematodes in farmed fallow deer (Dama dama L.)

The aim of the study was to determine the prevalence and intensity of infection with gastrointestinal nematodes in farmed fallow deer, and to assess the effectiveness of ivermectin used to control them.Faeces samples were collected from fallow deer (n = 468), raised on an organic farm.The study showed an average prevalence and intensity of infection with gastrointestinal nematodes in an annual cycle at 57.33 % and 529 EPG, respectively.Nematodes of the Trichostrongylus (13.33 %) and Chabertia (10 %) species were recorded most frequently, while Strongyloides sp.(3.33 %) had the lowest prevalence.Deworming was performed twice, in December and in March, during which a 1 % ivermectin injection was applied.The effi cacy of the fi rst deworming with ivermectin was 94.44 % and of the second deworming 95 %.The deworming did not result in removal of gastrointestinal nematodes in all hosts, but signifi cantly reduced the intensity of infection in these animals.Ivermectin, administered by subcutaneous injection, was highly effective against gastrointestinal nematodes in fallow deer.However, the deer were kept in a limited area, which caused the accumulation of eggs of gastrointestinal nematodes in the pasture sward, creating perfect conditions for reinvasion (ingestion of invasive forms with food).