East Tennessee Clinical Research, Inc., 80 Copper Ridge Farm Road, Rockwood, TN 37854, United States.
Vet Parasitol. 2010 Jul 15;171(1-2):106-10. doi: 10.1016/j.vetpar.2010.02.042. Epub 2010 Mar 3.
In recent years, numerous veterinary practitioners have reported anecdotal episodes in which anthelmintic treatment did not appear to deliver the expected efficacy against equine pinworms (Oxyuris equi). Anthelmintic resistance has not been demonstrated formally in equine pinworms, so a clinical study was designed to evaluate the efficacy of paste formulations of pyrantel pamoate or ivermectin against naturally acquired infections with O. equi. Twenty-one horses (>4 months to 15 years of age) with patent, naturally acquired pinworm infections were blocked by source of origin and allocated randomly to one of three treatment groups: horses (n=7) assigned to Group 1 were treated orally with pyrantel pamoate paste at a dosage of 13.2 mg/kg (2x label dosage), Group 2 horses (n=7) were untreated controls, and horses (n=7) assigned to Group 3 were treated orally with ivermectin paste at a dosage of 200 microg/kg. Fourteen days after treatment, horses were euthanatized, necropsied, and large intestinal contents were processed for recovery of adult pinworms. In addition, duplicate 1% aliquots of intestinal contents from the cecum, ventral colon, dorsal colon, and small colon were collected, preserved, and examined for recovery and enumeration of fourth-stage larval O. equi. Anthelmintic efficacy against pinworms was evaluated by comparing the post-treatment worm counts of Groups 1 and 3 to those of control animals. Mean numbers of O. equi adults recovered postmortem were significantly decreased by both pyrantel pamoate (P=0.0366) and ivermectin (P=0.0137) treatment, with respective efficacies of 91.2% and 96.0%. In addition, both products demonstrated >99% efficacy against fourth-stage O. equi larvae. The current study demonstrated acceptable adulticidal and larvicidal efficacy of both pyrantel pamoate and ivermectin paste formulations against O. equi and did not support the existence of macrocyclic lactone or pyrimidine resistance in the pinworm populations evaluated.
近年来，许多兽医报告了一些轶事，即在驱虫治疗中，马蛔虫（Oxyuris equi）似乎没有达到预期的疗效。马蛔虫尚未正式证明存在抗药性，因此设计了一项临床研究，以评估吡喹酮或伊维菌素糊剂对自然感染马蛔虫的疗效。21 匹（>4 个月至 15 岁）有明显、自然获得性蛔虫感染的马，按来源分为三组，随机分配到以下三个治疗组之一：第一组（n=7）口服 13.2mg/kg 吡喹酮糊剂（2x 标签剂量），第二组（n=7）为未治疗对照组，第三组（n=7）口服 200μg/kg 伊维菌素糊剂。治疗后 14 天，马被安乐死，进行尸检，并处理大肠内容物以回收成虫。此外，从盲肠、 ventral colon、dorsal colon 和 small colon 收集两份 1%的肠内容物，保存并检查第四期幼虫 O. equi 的回收和计数。通过比较治疗组 1 和 3 与对照组的治疗后蠕虫计数来评估驱虫剂对蛔虫的疗效。两种药物（吡喹酮和伊维菌素）处理后的马蛔虫成虫数量均显著减少（P=0.0366 和 P=0.0137），驱虫效果分别为 91.2%和 96.0%。此外，两种产品对第四期 O. equi 幼虫的疗效均超过 99%。本研究表明，吡喹酮和伊维菌素糊剂对马蛔虫具有良好的成虫杀灭和幼虫杀灭效果，并且未支持所评估的蛔虫种群存在大环内酯或嘧啶耐药性。
