Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Western Australia 6150, Australia.
Exp Parasitol. 2011 Sep;129(1):1-4. doi: 10.1016/j.exppara.2011.06.009. Epub 2011 Jul 2.
Cryptosporidium oocysts were inoculated into fresh dung (∼1.2×10(4) oocysts per gram wet weight) and fed to dung beetles to assess the effect of dung burial by the dung beetle Bubas bison on the distribution of the oocysts in small cores of soil in the laboratory. The experiment consisted of five replicates of each of two treatments; controls (dung but no dung beetles) and the experimental treatment (inoculated dung and seven pairs of dung beetles). After 5 days, when approximately 90% of the dung was buried, the surface and buried dung was recovered and subsampled. The oocysts in the subsamples were recovered and enumerated using qPCR. Oocyst viability was evaluated using an assay based on the exclusion or inclusion of two fluorogenic vital dyes, 4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI). Results revealed that overall 13.7% of oocysts remained on the surface and 86.3% of oocysts were buried. The viability of oocysts in buried dung was only 10% compared to oocysts the surface dung (58%). Therefore, widespread dung burial by B. bison during the winter months could substantially reduce the numbers of Cryptosporidium oocysts available to be washed into waterways following winter rains.
隐孢子虫卵囊被接种到新鲜的粪便（每克湿重约 1.2×10(4) 个卵囊）中，并喂食蜣螂，以评估蜣螂埋葬粪便对实验室中小土壤核心中卵囊分布的影响。该实验包括两种处理的五个重复；对照组（粪便但无蜣螂）和实验组（接种粪便和 7 对蜣螂）。5 天后，当大约 90%的粪便被掩埋时，回收并对表面和掩埋的粪便进行亚采样。使用 qPCR 回收和计数亚样本中的卵囊。通过基于两种荧光染料（4'，6-二脒基-2-苯基吲哚（DAPI）和碘化丙啶（PI）的排除或包含的测定来评估卵囊的活力。结果表明，总体上有 13.7%的卵囊仍在表面，86.3%的卵囊被掩埋。与表面粪便中的卵囊（58%）相比，埋藏粪便中的卵囊活力仅为 10%。因此，冬季 B. bison 广泛的粪便掩埋可能会大大减少冬季降雨后被冲入水道的隐孢子虫卵囊数量。
