Lack of efficacy of monepantel against trichostrongyle nematodes in a UK sheep flock
Lack of efficacy of monepantel against trichostrongyle nematodes in a UK sheep flock
复制标题
DOI：
10.1016/j.vetpar.2018.05.013
复制
发表时间：
2018-06-15
影响因子：
2.6
通讯作者：
Sargison, Neil
中科院分区：
文献类型：
--
作者：
Hamer, Kim;Bartley, Dave;Sargison, Neil
莫奈太尔耐药性是在对农场蛔虫控制策略的有效性进行常规监测时诊断出来的。尽管常规使用莫奈太尔，断奶的羔羊却变得节俭并出现腹泻。这种临床表现是由毛圆线虫病引起的。用 2.5mg/kg 莫奈太尔治疗后，粪便卵数减少了 76.7%（95% CI：55.1-82.2%）。通过对莫奈太尔处理前后粪便培养物和尸检中回收的幼虫池进行深度扩增子测序，鉴定出主要是玻璃性毛圆线虫以及少量的静脉食管线虫和玻璃性毛圆线虫。未分化的 FECRT 显示出对莫奈太尔的耐药性，但对左旋咪唑、伊维菌素或莫昔克丁没有耐药性。对农场驱虫治疗和动物移动记录的检查表明，在转移到青贮饲料之前进行的治疗，假定避难所中易感线虫的数量较少，可能对莫奈太尔抗性施加了很高的选择压力。使用驱虫药物有效控制寄生虫性胃肠炎是羊可持续生产的先决条件。该病例重申了将驱虫治疗与安全放牧相结合时的护理必要性，以及作为迭代计划动物健康管理一部分的驱虫药功效监测的价值。
Monepantel resistance was diagnosed during routine monitoring of the effectiveness of a farm's roundworm control strategy. Weaned lambs had become ill thrifty and developed diarrhoea, despite the routine use of monepantel. This clinical presentation was caused by trichostrongylosis. The faecal egg count reduction was 76.7% (95% CI: 55.1-82.2%) following treatment with 2.5mg/kg monepantel. Predominantly Trichostrongylus vitrinus along with small proportions of Oesophagostomum venulosum and Trichostrongylus vitrinus were identified by deep amplicon sequencing of pools of larvae recovered from pre and post monepantel treatment copro-cultures and on postmortem examinations. The undifferentiated FECRT showed resistance to monepantel, but not to levamisole, ivermectin, or moxidectin. Examination of farm anthelmintic treatment and animal movement records suggested that treatments before movement onto silage aftermaths, putatively with low numbers of susceptible nematodes in refugia, may have placed a high selection pressure on monepantel resistance. Effective control of parasitic gastroenteritis using anthelmintic drugs is a prerequisite for sustainable sheep production. This case reiterates the need for care when combining anthelmintic treatments with movements to safe grazing, and the value of monitoring of anthelmintic efficacy as part of iterative planned animal health management.