Development of resistance to eprinomectin in gastrointestinal nematodes in a goat herd with pre-existing resistance to benzimidazoles

• Published in: Polish journal of veterinary sciences Vol. 22; no. 4; pp. 753 - 760
• Main Authors: Mickiewicz, M, Czopowicz, M, Moroz, A, Szaluś-Jordanow, O, Górski, P, Várady, M, Königová, A, Spinu, M, Lefkaditis, M, Kaba, J
• Format: Journal Article
• Language: English
• Published: Germany Polish Academy of Sciences, Committee of Veterinary Sciences 01-12-2019
• Subjects: Animals; Anthelmintics - therapeutic use; Benzimidazoles; Benzimidazoles - pharmacology; Drug dosages; Drug Resistance; Eggs; Feces - parasitology; Goat Diseases - drug therapy; Goat Diseases - parasitology; Goats; Intestinal Diseases, Parasitic - drug therapy; Intestinal Diseases, Parasitic - parasitology; Intestinal Diseases, Parasitic - veterinary; Intestinal parasites; Ivermectin - analogs & derivatives; Ivermectin - therapeutic use; Laboratories; Lactones; Levamisole; Nematoda - drug effects; Nematode Infections - drug therapy; Nematode Infections - parasitology; Nematode Infections - veterinary; Nematodes; Parasite Egg Count; Parasitology; Pest resistance; Sheep; Poland; France; Germany; Haemonchus contortus; anthelmintic resistance; faecal egg count reduction test; levamisole; Trichostrongylus spp; goats; eprinomectin; Teladorsagia spp; larval development test
• ISSN: 1505-1773; 2300-2557
• DOI: 10.24425/pjvs.2019.131404

We described a first case of resistance to eprinomectin in goat herd in Poland in which resistance to benzimidazoles had been previously reported. The herd was established in 2011 by purchasing several goats from a single herd in south-eastern Poland. Resistance to benzimidazoles in the herd was first reported in 2017. Shortly after the owner started to signal low effectiveness of the treatment with eprinomectin. In June 2018 the larval development test from pooled faecal sample was performed and the results indicated the presence of resistance to macrocyclic lactones and levamisole. In July 2018 a faecal egg count (FEC) reduction test was performed in 39 animals with levamisole, eprinomectin and one untreated control group. Drugs were used in doses recommended for goats. Three methods of calculation of FEC reduction were compared. After eprinomectin treatment, FEC reduction ranged from 0 to 20%, depending on the method of calculation. FEC reduction following levamisole treatment was 100%. Main species present in the faecal samples after treatment and in larvicidal concentrations in larval development test was Haemonchus contortus. This is the first report of anthelminthic resistance to macrocylic lactones (eprinomectin) in goats in Poland.