Aim

This study assessed the feeding activity of the predatory nematode Butlerius butleri on the infective larvae of the sheep parasitic nematode Haemonchus contortus (Hc-L₃) and on two free-living nematodes Panagrellus redivivus (Pr) and Rhabditis sp. (R) in sterile sheep faecal cultures.

Materials and Methods

A bioassay was carried out in sheep faecal cultures, where predatory and prey nematodes were put together to assess the predatory behaviour on the different nematodes. Faecal cultures (n = 9) were set up in different treatments as follows: Treatments 1, 2 and 3 contained 20 specimens of B. butleri and 2000 Hc-L₃, Pr and R, respectively; treatments 4, 5 and 6, contained only 2000 Hc-L₃, Pr and R, respectively, as control groups. Treatment 7 contained 20 B. butleri as control. All treatments were incubated at room temperature for 30 days. The average number of nematodes recovered from each treatment was obtained and the reduction rate with respect to their corresponding control was estimated. Data were analysed using an ANOVA test using a completely randomised design in the SAS programme.

Results

Butlerius butleri reduced the Hc-L₃, population by 91.8%, whereas its population increased 131.6 times. The interactions between B. butleri and Pr and R resulted in 80.9% and 62.5% nematode reduction and B. butleri increased its populations 268.3 and 82.7 times, respectively. This experiment was performed only once, so this can be considered a preliminary report at this time.

Conclusion

This study provides evidence for the first time that B. butleri feeds on one of the most economically important nematodes of small ruminants, Hc-L₃.

Graphic Abstract

中文翻译：

---

Butlerius butleri (Nematoda: Diplogasteridae) 以 Haemonchus contortus (Nematoda: Trichostrongylidae) 实验室条件下绵羊粪便培养物中的感染性幼虫和自由生活线虫为食：初步报告。

目的

本研究评估了掠食性线虫Butlerius butleri对绵羊寄生线虫Haemonchus contortus ( Hc-L ₃ ) 和两种自由生活线虫Panagrellus redivivus ( Pr ) 和Rhabditis sp.的感染性幼虫的摄食活动。( R ) 在无菌绵羊粪便培养物中。

材料和方法

在绵羊粪便培养物中进行了生物测定，其中将捕食性线虫和猎物线虫放在一起以评估对不同线虫的捕食行为。粪便培养物 ( n  = 9) 在不同处理中设置如下：处理 1、2 和 3 分别包含 20 个B. butleri和 2000 Hc-L ₃、Pr和R；处理 4、5 和 6 分别仅含有 2000 个Hc-L ₃、Pr和R作为对照组。处理 7 含有 20 个B. butleri作为控制。所有处理均在室温下孵育 30 天。获得从每个处理中回收的线虫的平均数量，并估计相对于它们相应的控制的减少率。使用 SAS 程序中完全随机设计的方差分析测试对数据进行分析。

结果

Butlerius butleri将Hc-L ₃种群减少了 91.8%，而其种群增加了 131.6 倍。B. butleri与Pr和R之间的相互作用导致线虫减少 80.9% 和 62.5%，B. butleri 的数量分别增加了 268.3 和 82.7 倍。这个实验只进行了一次，所以这在这个时候可以被认为是一个初步的报告。

结论

这项研究首次提供了证据，表明B. butleri以一种经济上最重要的小型反刍动物线虫Hc-L ₃为食。

图形摘要