PARENTERALLY ADMINISTERED IVERMECTIN - EF FICACY AGAINST NEMATODES INMOUFLON (OVIS MUSIMON)

During the direct handling with mouflon the ivermectin (IVM) is usuall y parenterally administered. The used dose is equal to dose recommende d to domestic sheep (0.20 mg/kg of body weight). The qualitative and q uantitative parasithological differences between domestic and wild she ep (mouflon) exist (Vyslouzil, 1985; Lochman et al., 1979; Boch and Su pperer, 1992). The verification of real anthelmintic efficacy in IVM t reatment of mouflon was not realized up to now. The aim of this study was to describe anthelmintic efficacy of IVM administered in different doses and to select the optimum dose. The study was realized during w inter season in game herd in 23 mouflons of 10-11 months old. Before t reatment larvae of Muellerius capillaris (strong infection) and eggs o f Nematodirus spp. and Oesophagostomum spp. (mild infection) in common faecal samples were found. The mouflons were randomly divided in four groups (control group (3 head) and 3 experimental groups (6-8 animals in group). Before experimental treatment each animal in experimental groups was weighted and marked. The doses of IVM 0.20, 0.60, and 1.00 mg/kg of body weight were used. The drug was administered subcutaneous ly. All mouflons were placed into enclosured area of 4 hectare. 28-60 days after treatment mouflon were hunted and detail helminthological e xaminations (lung macroscopical evaluation, larvoscopy of lung vermino us spots, larvoscopy and ovoscopy of individual faeces, necropsy of ga strointestinal organs and quantification of nematode adults) were carr ied out. LPG and EPG values were determined. The study was realized as a simple blind experiment-all helminthological examinations were done without knowledge of the used therapy (control x experimental animals ) or IVM dose (experimental animals). Macroscopical examinations of lu ngs showed symptoms of strong M. capillaris infection (numerous vermin ous spots) in all 23 mouflons. Larvoscopical examinations (lung tissue , individual faeces) after treatment became negative in 19 treated ani mals, in the rest of animals the mild larvoscopical finding was determ ined (Tab. I). Pretreatment common LPG values ten 2100-2230) in contro l animals were confirmed, findings in verminous spats of these animals were highly positive (massive presence of live larvae, eggs, and rest s of nematode adults). The qualitative findings (quantitatively were f indings under the detection limit for the used method) were minimum in 4 mouflons of all treated groups. Pretreatment ovoscopical findings i n control animals were confirmed, too. Necropsy examinations of gastro intestinal organs were highly positive in all control animals (mean fi nding of 95 adults of determined nematodes), in treated animals the fi ndings were positive in 3 animals of different groups (up to 2 adults only). In respect to reached results, pathogenity of found nematodes, age of experimental mouflons, and economy of treatment, a dose of 0.60 mg/kg of body weight IVM dose as a optimum for parenteral treatment o f mouflon nematodoses is recommented.