[Efficacy of mebendazole on Elaphostrongylus rangiferi in reindeer (author's transl)].

Elaphostrongylus rangiferi is a very common parasite in Scandinavian reindeer, causing losses due to cerebral nematodiasis and granulomatous parasitic pneumonias and also causing a discard of parts of the carcass at meat inspection. In limited experiments, the efficacy of mebendazole on E. rangiferi has been tested. It was found that daily treatment during a period of 10 days with 6 mg/kg body weight, given as medicated feed, resulted in a decreased fecal larval count at the 10th day and a total cessation of excretion of larvae at the 43rd day, indicating a good anthelmintic effect of mebendazole on E. rangiferi. Single dose treatment with 40 mg/kg body weight was not adequate against E. rangiferi. This dose level, however, completely eliminated excretion of gastrointestinal parasite eggs, as did the 10 day treatment with 6 mg/kg body weight of mebendazole. This dose is double that of the recommended dose for wild ruminants and the need of higher dose is discussed to be due to the dominance of older females of the flock, giving less access to the food for the low-ranked animals. Long-time treatment of reindeer, comparable to the method used, is possible during periods of supplementary feeding during spring-time and then not interfering with the normal management. Deworming will then also intervene with the peak of larvae excretion. Thus it seems possible to considerably decrease the number of larvae on the pastures.