Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany.
Parasitol Res. 2022 May;121(5):1539-1543. doi: 10.1007/s00436-022-07485-9. Epub 2022 Mar 15.
The examination of feces for stages of parasitic helminths is the most widely used methodology for the intravital diagnosis in domestic animals of patent endoparasitism including pulmonary nematode infections. Although there is only little information on the relationship of lungworm larval excretion and corresponding parasite burdens, fecal larval counts are used as indirect measure ("biomarker") for the intensity of infection, for instance in anthelmintic efficacy studies. To assess the relationship between fecal larval and Protostrongylus rufescens parasite counts in sheep, log-transformed data of 14 naturally infected animals were analyzed. The larval excretion of the sheep was monitored in approximately weekly intervals over 6 weeks before lungworm recovery. Analyses were performed on the larval counts (at a single time point or counts averaged over several consecutive time points) relating to parasite counts. Fecal larval counts and the P. rufescens nematode burden (range, 17 to 406) were significantly and strongly correlated (p < 0.05 for all analyses; Spearman's r > 0.6) with the number of larvae excreted increasing with increasing lungworm burden. Subsequently performed regression analysis demonstrated a statistically significant strong linear relationship between P. rufescens worm and fecal larval counts (p < 0.01 for all analyses; R, range 0.5094 to 0.8150). Analyses based on larval counts averaged over two or more consecutive time points resulted in higher Spearman's r and R compared with analyses based on single time point larval counts. Despite of some variability, the analyses indicate that fecal larval counts can be regarded as a useful measure of the P. rufescens burden in sheep.
检查粪便中的寄生虫幼虫阶段是在国内动物体内进行活体诊断最广泛使用的方法，包括肺线虫感染。尽管有关肺蠕虫幼虫排泄和相应寄生虫负担之间的关系的信息很少，但粪便幼虫计数被用作感染强度的间接测量（“生物标志物”），例如在驱虫效果研究中。为了评估绵羊粪便幼虫和旋毛虫幼虫计数之间的关系，对 14 只自然感染的动物的对数转换数据进行了分析。在肺蠕虫恢复之前，在大约 6 周的时间内，每周监测一次绵羊的幼虫排泄情况。分析了与寄生虫计数相关的幼虫计数（在单个时间点或连续多个时间点的平均计数）。粪便幼虫计数和旋毛虫线虫负担（范围为 17 至 406）之间存在显著的强相关性（所有分析的 p 值均小于 0.05；Spearman r 值大于 0.6），随着肺蠕虫负担的增加，排出的幼虫数量增加。随后进行的回归分析表明，旋毛虫蠕虫和粪便幼虫计数之间存在统计学上显著的强线性关系（所有分析的 p 值均小于 0.01；R 值范围为 0.5094 至 0.8150）。基于两个或更多连续时间点的幼虫计数平均值进行的分析与基于单个时间点幼虫计数的分析相比，Spearman r 和 R 值更高。尽管存在一些可变性，但这些分析表明，粪便幼虫计数可以作为绵羊旋毛虫负担的有用衡量标准。
