The objective of the present study was to determine the susceptibility of entomopathogenic nematodes to ivermectin and thiabendazole. Soil samples collected from the municipalities of Irapuato and León, Guanajuato, Mexico, were obtained, from which the entomopathogenic nematodes (EPNs) of the Steinernematidae and Heterorhabditidae families were isolated. The samples were classified from livestock and nonlivestock soils, and the susceptibility of EPNs to anthelmintics was determined with the larval motility assay (LMA, 24 h) and the larval migration inhibition assay (LMI assay, 48 h). Sterile distilled water (T1) and treatments with 1% ivermectin diluted in 5% DMSO (dimethyl sulfoxide) (T2) and 5% thiabendazole diluted in 5% DMSO (T3) were applied to infective juvenile larvae. Analysis of variance was performed with a factorial design and Tukey's test at 0.05 probability. In addition, different concentrations of ivermectin (0.1, 0.5, 1, 1.2, 1.5, and 2 μg) and thiabendazole (1, 5, 10, 12, 15, and 20 mg) were evaluated to perform a Probit analysis to determine their LC50. All strains of EPNs were susceptible to ivermectin in both the LMA and LMI assay. The results show that EPNs are susceptible to ivermectin and thiabendazole, and the degree depends on the type of test performed, the chemical product used, and the origin of the strain of EPN.

中文翻译：

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昆虫病原线虫对伊维菌素和噻菌灵的敏感性。

本研究的目的是确定昆虫病原线虫对伊维菌素和噻菌灵的敏感性。获得了从墨西哥瓜纳华托州伊拉普阿托市和莱昂市收集的土壤样本，从中分离出了Steinernematidae科和Heterorhabditidae科的致病性线虫（EPN）。从牲畜和非牲畜土壤中对样品进行分类，并通过幼虫活力试验（LMA，24小时）和幼虫迁移抑制试验（LMI试验，48小时）确定EPN对驱虫药的敏感性。将无菌蒸馏水（T1）以及在5％DMSO（二甲基亚砜）（T2）中稀释的1％伊维菌素和在5％DMSO（T3）中稀释的5％噻菌灵处理用于感染性幼虫。方差分析是通过阶乘设计和Tukey' s检验的概率为0.05。此外，评估了不同浓度的伊维菌素（0.1、0.5、1、1.2、1.5和2μg）和噻苯达唑（1、5、10、12、15和20 mg）进行Probit分析以确定其LC50 。在LMA和LMI分析中，所有EPN菌株均对伊维菌素敏感。结果表明，EPN对伊维菌素和噻菌灵敏感，其程度取决于所进行的测试类型，所使用的化学产品以及EPN菌株的来源。