The efficacy of ivermectin against helminth and arthropod parasites of impala.

The efficacy of ivermectin, injected subcutaneously at a dosage rate of 200 mcg/kg live mass, was determined against nematodes, ixodid ticks and lice infestations acquired by free-living impala, Aepyceros melampus, in the Kruger National Park. Although the parasite burdens of the untreated control animals varied considerably, ivermectin appeared to be highly effective against 7 nematode species and effective against 3 others. Of the 4 tick species recovered, only Boophilus decoloratus appeared to have been affected. In the case of the lice infestations, ivermectin was highly effective against 3 species of Linognathus, but ineffective against the 2 Damalinia species present.