Evaluation of the efficacy of solid dispersion of fenbendazole against different stages of gastrointestinal nematodes of sheep in Samara region

Abstract

The purpose of the research is to study the efficacy of a solid dispersion of fenbendazole at different stages of gastrointestinal nematodes of young sheep. Materials and methods. Evaluation of the efficacy of a solid dispersion of fenbendazole at different stages of gastrointestinal nematodes was carried out in the farms of the Samara region on 35 sheep aged 7–10 months naturally infected with gastrointestinal strongylates. Animals were divided into experimental and control groups of 8-9 animals each. A solid dispersion of fenbendazole was administered once orally at a dose of 2.0 mg/kg of active substance to the animals of the first experimental group. Animals of the 2nd group received the substance of fenbendazole at a dose of 2 mg/kg. The basic drug – Panakur was administered to the sheep of the 3rd experimental group at a dose of 5 mg/kg. Animals of the control group did not receive the drugs. The efficacy of the drugs was calculated in the experiment of «control test» based on the results of coproovoscopic examination, as well as on the results of helminthological necropsy of the digestive tract of animals, 3–5 sheep from each group. Results and discussion. The solid dispersion of fenbendazole showed 97.8–98.2% efficacy against adult strongylates and 80.6–87.5% against larvae. The substance of fenbendazole at the same dose – 2 mg/kg revealed 33.0–41.7% and 16.1–26.9% efficacy respectively. The basic drug Panakur showed 95.4–97.3% and 46.7–73.9% efficacy against imaginal strongylates and larvae respectively at a dose of 5.0 mg/kg of active substance.