Anthelmintic resistance of gastrointestinal nematodes in sheep, Mato Grosso do Sul, Brazil.

作者：Sczesny Moraes Eurico A^*; Bianchin Ivo; da Silva Karina F; Catto Joao Batista; Honer Michael Robin; Paiva Fernando

来源：Pesquisa Veterinaria Brasileira, 2010, 30(3): 229-236.

• Parasites
• Haemonchus
• treatments
• control
• small ruminants

Sczesny-Moraes E.A., Bianchin I., Silva K.F., Catto J.B., Honer M.R. & Paiva F. 2010.[Anthelmintic resistance of gastrointestinal nematodes in sheep, Mato Grosso do Sul, Brazil.] Resistencia anti-helmintica de nematoides gastrintestinais em ovinos, Mato Grosso do Sul. Pesquisa Veterinaria Brasileira 30(3):229-236. Departamento de Patologia, Centro de Ciencias Biologicas e da Saude, Universidade Federal de Mato Grosso do Sul, Cidade Universitaria, Campo Grande, MS 79070-900, Brazil. E-mail: [e-mail]
Among the methods of control of gastrointestinal worms in sheep, the use of chemicals is the most common. However, the continued, and indiscriminate, use of these products has selected populations of resistant helminths to anthelmintics, a phenomenon reported in the whole world. This study aimed to identify the species of gastrointestinal parasites and diagnose the status of anthelmintic resistance in sheep in the State of Mato Grosso do Sul Brazil. Feacal egg count reduction tests (FECRT) were performed in flocks of sixteen farms, and the seven formulations used contained the following pharmacological bases: Albendazole, Ivermectin, Levamizol, Trichlorfon, Moxidectin, Closantel and one containing the first three in association. The species identified at necropsy, in adult sheep, were: Haemonchus contortus, Trichostrongylus colubriformis, Cooperia curticei, C. punctata, C. pectinata and Oesophagostomum columbianum, in order of prevalence. The formulations containing Albendazole and Ivermectin did not show efficacy in reducing the EPG in the flocks tested, with average reductions of 0.7 and -19.6%, respectively. Closantel presented an average efficacy of 6.7%; Levamisolee, Moxidectin and Trichlorfon, 28.7, 26.8 and 65% respectively, the combination of three bases (Albendazole, Ivermectin and Levamizol), an average efficacy of 55.8 %. The average percentages of infective larvae recovered in the faecal cultures, pre and post treatment were similar, indicating that resistance to the bases tested is present in all species cited, to a greater or lesser degree. The two genera predominantly resistant are Haemonchus sp., with 86.9%, followed by Trichostrongylus sp., with an average of 47.5%, Strongyloides sp. 33.6%, Oesophagostomum sp. 21.4% and Cooperia sp. 19.7%.

• 出版日期2010-3