ABSTRACT The aim of this study was to perform in vitro screening of the antiparasitic potential of thirty-five plant extracts against the gastrointestinal nematode (GIN) Haemonchus contortus and the cattle tick Rhipicephalus microplus. The larval development test (LDT) and egg hatch test (EHT) were performed to assess the activity against GIN; and the larval packet test (LPT), larval repellency test (RT) and adult immersion test (AIT) were used to assess the acaricidal effect. In the EHT, the Senecio brasiliensis aqueous extract had the best IC50 value (1.2 mg.mL-1). In the LPT and AIT, Schinus lentiscifolius hexane extract presented best acaricidal effect, with 100% efficacy at 50 mg.mL-1 and IC50 of 2.1 mg.mL-1, respectively. In summary, S. brasiliensis demonstrated potential for the control of GIN, while S. lentiscifolius showed outstanding efficacy against cattle tick, therefore both have potential for future studies related to isolation of bioactive substances and toxicological and pre-clinical experiments.

中文翻译：

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植物提取物对 Haemonchus contortus 和 Rhipicephalus (Boophilus) microplus 的体外筛选

摘要 本研究的目的是对 35 种植物提取物对胃肠道线虫 (GIN) Haemonchus contortus 和牛蜱 Rhipicephalus microplus 的抗寄生虫潜力进行体外筛选。进行幼虫发育试验（LDT）和卵孵化试验（EHT）以评估对GIN的活性；幼虫包试验（LPT）、幼虫驱避试验（RT）和成虫浸泡试验（AIT）用于评估杀螨效果。在 EHT 中，巴西千里光水提物的 IC50 值最好（1.2 mg.mL-1）。在 LPT 和 AIT 中，香樟提取物的杀螨效果最好，50 mg.mL-1 时的杀螨效果为 100%，IC50 为 2.1 mg.mL-1。总之，S. brasiliensis 展示了控制 GIN 的潜力，而 S.