Goodroe Anna E, Baxter Victoria K, Watson Julie
Research Animal Resources, Johns Hopkins School of Medicine, Baltimore, Maryland, USA; Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
J Am Assoc Lab Anim Sci. 2016;55(5):541-7.
Aspiculuris tetraptera continues to be a problem in rodent vivaria, in part due to difficulties in parasite detection. Although PCR testing is highly sensitive, it is expensive and does not always provide immediate results. Consequently, many institutions rely on passive fecal flotation as a quick inhouse exam for diagnosing A. tetraptera infections. To increase the sensitivity of this test, we examined multiple parameters to determine the optimal test protocol. A 30-min soaking period prior to fecal flotation for 15 min allowed fecal pellets to soften and facilitated efficient egg isolation. We also evaluated the effect of time of day, sample size, age, sex, and housing status on egg isolation. No evidence of cyclical egg shedding was found, and although larger fecal sample sizes did not result in more eggs isolated, their use reduced the incidence of false-negative exams. The most eggs were isolated from 8- and 12-wk-old mice, and as mice aged, the number of eggs isolated declined. Overall, neither sex nor housing status influenced the number of eggs isolated. Finally, examination of multiple diagnostic tests (fecal flotation exam, direct examination of cecal and colonic contents, and fecal PCR) revealed that no single test was definitive, thus indicating that multiple tests might be required to successfully screen mice with low pinworm burdens. These findings provide guidance regarding sample selection, collection, and processing to efficiently detect A. tetraptera.
四翼无刺线虫仍然是啮齿动物饲养室中的一个问题，部分原因是寄生虫检测存在困难。尽管聚合酶链反应（PCR）检测高度灵敏，但成本高昂且并非总能立即得出结果。因此，许多机构依靠被动粪便漂浮法作为一种快速的内部检测方法来诊断四翼无刺线虫感染。为了提高该检测的灵敏度，我们研究了多个参数以确定最佳检测方案。在进行15分钟粪便漂浮之前先浸泡30分钟，可使粪便颗粒软化并有助于高效分离虫卵。我们还评估了一天中的时间、样本量、年龄、性别和饲养状态对虫卵分离的影响。未发现虫卵排出有周期性迹象，虽然较大的粪便样本量并未导致分离出更多虫卵，但使用较大样本量可降低假阴性检测的发生率。从8周龄和12周龄小鼠中分离出的虫卵最多，随着小鼠年龄增长，分离出的虫卵数量减少。总体而言，性别和饲养状态均未影响分离出的虫卵数量。最后，对多种诊断检测方法（粪便漂浮检查、盲肠和结肠内容物直接检查以及粪便PCR）的研究表明，没有一种检测方法是决定性的，因此表明可能需要进行多种检测才能成功筛查蛔虫负担较低的小鼠。这些发现为有效检测四翼无刺线虫的样本选择、采集和处理提供了指导。
