Novartis Centre de Recherche Santé Animale SA, CH-1566 St-Aubin, Switzerland.
Vet Parasitol. 2010 Jun 24;170(3-4):336-9. doi: 10.1016/j.vetpar.2010.02.011. Epub 2010 Feb 18.
In the presence of multiple anthelmintic resistance, effective quarantine treatment of sheep entering a farm has become a crucial tool in nematode management. In the present work, the use of the amino-acetonitrile derivative, monepantel as a quarantine treatment was investigated. Of special interest was the rapidity of decrease in fecal egg counts (FEC) compared to other anthelmintics used in sheep. In three different studies, sheep were either infected with Haemonchus contortus of known resistance status or with a panel of susceptible and multi-resistant gastro-intestinal nematodes. Fecal egg counts were determined from several hours up to 14 days after treatment with monepantel, benzimidazoles, levamisole, macrocyclic lactones or combinations of the latter three classes. The treatment of susceptible isolates with effective anthelmintics, either as single or combined applications caused a reduction of FEC to 0 within 3-4 days. The status of the resistant nematodes could be confirmed, as treatment with the affected classical anthelmintics never resulted in complete absence of parasite eggs in all samples analyzed. In the case of multi-resistant isolates, only monepantel was able to stop egg excretion, while all other treatments resulted in only a partial reduction of FEC. The resistance status of the nematodes did not influence the rapid decline of egg counts after treatment with monepantel.
在存在多种驱虫药耐药性的情况下，对进入农场的绵羊进行有效的检疫治疗已成为线虫管理的重要工具。在目前的工作中，研究了使用氨基乙腈衍生物莫能菌素作为检疫处理。特别感兴趣的是与绵羊中使用的其他驱虫药相比，粪便虫卵计数（FEC）迅速下降。在三项不同的研究中，绵羊要么感染了具有已知耐药性的捻转血矛线虫，要么感染了一组易感性和多耐药性的胃肠线虫。在用莫能菌素、苯并咪唑类、左旋咪唑、大环内酯类或后三类组合治疗后数小时至 14 天内，从粪便中检测到虫卵计数。用有效驱虫药治疗易感分离株，无论是单一应用还是联合应用，都能在 3-4 天内将 FEC 降低到 0。耐药线虫的状况可以得到确认，因为受影响的经典驱虫药治疗从未导致所有分析样本中寄生虫卵完全消失。在多耐药分离株的情况下，只有莫能菌素能够停止卵排泄，而所有其他治疗方法仅导致 FEC 的部分减少。线虫的耐药性状况并不影响莫能菌素治疗后卵计数的迅速下降。
