Clinical ef®cacy of fenbendazole against gastrointestinal parasites in llamas

Llamas or South American Camelids (SACs) are increasingly popular in the United States, as a source of ®ber, livestock guard, and pack animals. Gastrointestinal parasites have been identi®ed as a major health problems in all classes of livestock including llamas. Currently there are no approved anthelmintics available for use in llamas. In this study, fenbendazole was evaluated for its clinical ef®cacy in the control of gastrointestinal parasitism in llamas. Twelve, healthy, young adult llamas of both sexes naturally infested with Nematodirus, Strongyloides, Trichuris, and Capillaria were randomly divided into two groups. One group received a single oral dose of fenbendazole paste at 5 mg/kg. The second group received a comparable dose of water as a placebo. Fecal samples were obtained per rectum from each animal prior to administration of either the drug or placebo treatment and weekly thereafter. These samples were analyzed for total fecal egg burden using a modi®ed Wisconsin sugar ̄oatation technique. The fenbendazole treated group had a signi®cant reductions in total fecal egg counts of 95%, 84%, 89% and 76%, respectively, for each week of the four-week sampling period. Nematodirus, Strongyloides, and Trichuris all had signi®cant reductions in egg counts during the study period All animals were observed twice daily during the experiment. All animals remained healthy and showed no adverse effects related to treatment. These results indicate that fenbendazole is a safe and an effective anthelmintic for the treatment of naturally occurring gastrointestinal parasite infestations of Nematodirus, Strongyloides, and Trichuris in llamas. # 2000 Published by Elsevier Science B.V. All rights reserved.