First report of monepantel Haemonchus contortus resistance on sheep farms in Uruguay

Particle and Fibre Toxicology

Georgget E Banchero²  Zully Ramos¹  América E Mederos¹ 

[1] Beef and Wool Program, National Research Institute for Agriculture (INIA), Ruta 5 Km 386, Tacuarembó 45000, Uruguay;Beef and Wool Program, National Research Institute for Agriculture (INIA), La Estanzuela, Ruta 50 Km 11, Colonia, Uruguay

关键词: Uruguay;    Haemonchus contortus;    Anthelmintic resistance;    Monepantel;    Sheep;   

Others  :  1148327
DOI  :  10.1186/s13071-014-0598-z

 received in 2014-08-29, accepted in 2014-12-09,  发布年份 2014

【 摘 要 】

Background

On two farms it was noted that after routine treatment with monepantel, fecal egg counts failed to drop. This was accompanied by lambs mortality due to Haemonchus contortus infection. The aim of this work was to evaluate the efficacy of monepantel to control gastrointestinal nematodes (GIN) in two sheep farms, in Uruguay.

Findings

A Fecal Egg Count Reduction Test (FECRT) was subsequently performed at the Experimental Stations Glencoe of INIA Tacuarembó (Farm 1) and Sheep Unit of INIA La Estanzuela (Farm 2) using the World Association for the Advancement of Veterinary Parasitology guidelines. On Farm 1 the FECRT was performed using 6–8 month old Corriedale or Merino Dohne x Corriedale male lambs naturally infected with GIN. On day 0 pre-treatment, three groups of 15 lambs each were selected, blocked by fecal egg count level (FEC) and randomly assigned to one of the following: Group 0 = untreated control, Group 1 = treated with monepantel (Zolvix®, Novartis Animal Health Inc.) from stock previously purchased; Group 2 = treated with monepantel from stock provided by the supplier, at the recommended dose of 2.5 mg/kg of body weight. Fecal samples were collected directly from the rectum from each lamb on day 0 and on day 9 post-treatment. On Farm 2, the FECRT was conducted on a group of 8 month old male lambs Milchschaff x Finn. At this farm, 10 lambs were randomly allocated to be treated with monepantel (Group 1) and 10 lambs were randomly allocated to remain as untreated control (Group 0) using the same protocols as Farm 1.

On farm 1 the FECR was 0.0% (95% CI = 0.0 – 49.0) and 42.0% (95% CI = 0.0 – 75.0) for Group 1 and Group 2 respectively. For Farm 2, the FECR was 82.1% (95% CI = 36.0 – 99.0). Haemonchus spp was the resistant genus.

Conclusions

Poor effcicacy of monepantel in treating GIN parasites was demonstrated on both farms.

【 授权许可】

   
2014 Mederos et al.; licensee BioMed Central.

【 参考文献 】

• [1]Nari A, Salles J, Gil A, Waller PJ, Hansen JW: The prevalence of anthelmintic resistance in nematode parasites of sheep in southern Latin America: Uruguay. Vet Parasitol 1996, 62:213-222.
• [2]Mederos A, Gallinal M, González H, Silva L, Rodriguez S: Diagnóstico de resistencia a los antihelmínticos en ovinos en Uruguay. In Resumen del 12° Simposio Internacional de la Asociación Mundial de Laboratorios de Diagnóstico Veterinario (WAVLD). Montevideo, Uruguay: Sociedad de Medicina Veterinaria del Uruguay 2005.
• [3]Kaminsky R, Ducray P, Jung M, Clover R, Rufener R, Bouvier J, Schorderet Weber S, Wenger A, Wieland-Berghausen S, Goebel T, Gauvry N, Pautrat F, Skripsky T, Froelich O, Komoin-Oka C, Westlund B, Sluder A, Mäser P: A new class of anthelmintic effective against drug-resistant nematodes. Nature 2008, 452:176-180.
• [4]Scott I, Pomroy B, Paul K, Greg S, Barbara A, Moss A: Lack of efficacy of monepantel against Teladorsagia circumcincta and Trichostrongylus colubriformis. Vet Parasitol 2013, 198:166-171.
• [5]Van Wyk JA, Bath GF: The FAMACHA system for managing haemonchosis in sheep and goats by clinically identifying individual animals for treatment. Vet Res 2002, 33:509-529.
• [6]Vatta AF, Letty BA, van der Linde MJ, Krecek RC: Testing of a chart for the diagnosis of ovine clinical anaemia caused by haemonchosis for use in goats farmed under resource-poor conditions in South Africa. In FAO TCP Workshop on Sustainable Worm Control Programmes for Sheep and Goats. Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa; 2000.
• [7]Coles GC, Bauer C, Borgsteede FHM, Geerts S, Klei TR, Taylor MA, Waller PJ: World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) methods for the detection of anthelmintic resistance in nematodes of veterinary importance. Vet Parasitol 1992, 44:35-44.
• [8]Coles GC, Jackson F, Pomroy WE, Prichard RK, von Samson-Himmelstjerna G, Silvestre A, Taylor MA, Vercrsuysse J: The detection of anthelmintic resistance in nematodes of veterinary importance. Vet Parasitol 2006, 136:167-185.
• [9]Ministry of Agriculture, Fisheries, Food (MAFF): Manual of Veterinary Parasitological Laboratory Techniques. Ministry of Agriculture, Fisheries and Food, London; 1986.
• [10]Van Wyk JA, Mayhew E: Morphological identification of parasitic nematode infective larvae of small ruminants and cattle: A practical lab guide. Onderstepoort J Vet Res 2013, 80:1-14. doi:10.4102/ojvr.v80i1.539
• [11]Dash K, Hall K, Barger IA: The role of arithmetic and geometric worm egg counts in faecal egg count reduction test and in monitoring strategic drenching programs in sheep. Aust Vet J 1988, 65:66-68.
• [12]Cabaret J, Antoine T: In Anthelmintics. Clinical Pharmacology, uses in veterinary medicine and efficacy. W. Quick Ed. Nova, New York: Nova science publisher; 2014. p. 1-26.
• [13]Rufener L, Mäser P, Rodit I, Kaminsky R: Haemonchus contortus acetylcholine receptors of the DEG-3 subfamily and their role in sensitivity to monepantel. PLos Pathogens 2009, 5:1-11.
• [14]Roeber F, Jex AR, Gasser RB: Impact of gastrointestinal parasitic nematodes of sheep, and the role of advanced molecular tools for exploring epidemiology and drug resistance - an Australian perspective. Parasit Vectors 2013, 6:153. BioMed Central Full Text
• [15]Falzon LC, O’Neill TJ, Menzies PI, Peregrine AS, Jones-Bitton A, van Leeuwen J, Mederos A: A systematic review and meta-analysis of factors associated with anthelmintic resistance in sheep. Prev Vet Med 2014, 17:388-402.