Development and Application of Nested PCR Assay for Detection of Dairy Cattle-Derived Cyclospora sp.

To develop a nested PCR assay for the detection of cattle-derived Cyclospora sp.,two pairs of primers were designed on the basis of the cattle-derived Cyclospora sp.sequences.These primers selectively amplified a 168-bp DNA fragment of the 18S rRNA gene of cattle-derived Cyclospora sp.With these primers,a nested PCR assay for the detection of cattlederived Cyclospora sp.was developed.The nested PCR assay was specific and there is no cross-reaction with other parasites,such as Eimeria spp.,Cryptosporidium spp.,Giardia sp.,Toxoplasma sp.,Trichuris sp.and cattle ciliate.The assay was able to detect as low as 2.85 x 10-2 fg of the control positive DNA.The results of the detection of clinical samples indicated that the assay coincided with microscopic examination.The results show that the nested PCR assay will be an effective tool for the detection of Cyclospora sp.in cattle feces.