Johnson Alexa C B, Biddle Amy S
Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716, USA.
Animals (Basel). 2021 May 9;11(5):1345. doi: 10.3390/ani11051345.
Cyathostomins are a multispecies parasite ubiquitous in Equids. Cyathostomins have developed resistance to all but one class of anthelmintics, but species-level sensitivity to anthelmintics has not been shown. This study measured reinfection rates of cyathostomin species following the administration of three commercial dewormers. Nine treated horses were compared with 90 untreated controls during June-September 2017-2019. Ivermectin (IVM) (n = 6), Moxidectin (MOX) (n = 8) or Pyrantel (PYR) (n = 8) were orally administered. Fecal samples were collected every 14 d for 98 d. Fecal egg count reductions (FECR) were calculated using a modified McMaster technique. Nineteen cyathostomin species were identified by 5.8S-ITS-2 profiling using amplicon sequencing. Data were analyzed in QIIME1 and R statistical software using presence/absence methods. MOX had the lowest numbers of species present over the time course, followed by PYR then IVM (7.14, 10.17, 11.09, respectively); however, FECR was fastest for PYR. The presence of seven species: and were unaffected by treatment ( > 0.05) points to species-specific differences in dewormer sensitivity and environmental persistence. Identifying resistance patterns at the species level will enable mechanistic understandings of cyathostomin anthelmintic resistance and targeted approaches to control them.
圆线虫是一种在马属动物中普遍存在的多物种寄生虫。除一类驱虫药外，圆线虫已对所有其他驱虫药产生了抗性，但尚未显示出其对驱虫药的种水平敏感性。本研究测定了三种市售驱虫药给药后圆线虫物种的再感染率。在2017年至2019年6月至9月期间，将9匹接受治疗的马与90匹未治疗的对照马进行了比较。口服伊维菌素（IVM）（n = 6）、莫西菌素（MOX）（n = 8）或吡喹酮（PYR）（n = 8）。每14天采集粪便样本，持续98天。使用改良的麦克马斯特技术计算粪便虫卵计数减少率（FECR）。通过扩增子测序的5.8S-ITS-2分析鉴定了19种圆线虫物种。使用存在/缺失方法在QIIME1和R统计软件中分析数据。在整个时间过程中，MOX存在的物种数量最少，其次是PYR，然后是IVM（分别为7.14、10.17、11.09）；然而，PYR的FECR最快。七种物种： 和 的存在不受治疗影响（> 0.05），这表明驱虫药敏感性和环境持久性存在物种特异性差异。在物种水平上确定抗性模式将有助于从机制上理解圆线虫的驱虫药抗性以及控制它们的靶向方法。
