DPIRD approved fluke egg sedimentation test (FEST) procedure

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8. Results

Trematode eggs and coccidian oocysts remain unstained and stand out clear against the bluish stained vegetable matter.

8.1 Calculations

Eggs per gram of faeces equals to total number of eggs counted divided by total amount in grams of faeces examined

8.2 Units

Eggs/g faeces


The oocysts of Eimeria leuckarti are 71–85 micron x 51–63 micron in size and have a 7–9 micron thick dark brown exterior shell with a rough surface. The interior sheath is colourless with a distinct micropyle.

Fasciola hepatica eggs are 140 micron x 80 micron, golden yellow with an indistinct operculum and the embryonic cells are also rather indistinct. They must be distinguished from the eggs of other flukes, especially the large eggs of paramphistomes, which are of the same size. The paramphistomes are 120–180 micron x 70–90 micron (depending on species), have transparent shells and distinct opercula; their embryonic cells are clear and there is frequently a small knob at the posterior pole and they are pale brown to grey in colour.

Mite eggs can be of similar size as trematode eggs and are sometimes difficult to differentiate from liver fluke eggs. They are usually darker yellow, orange or even brown and slightly asymmetrical with very distinct embryonic cells. Most mite eggs have no operculum, but some do. The operculum, when present, is very distinct, and usually well within the upper third of the shell.

9. Validation

Modified technique, validation report attached (Appendix 1).

10. Reference ranges

Not applicable.

11. Reporting

Reported only as positive or negative for Fasciola hepatica, paramphistomes or Eimeria leuckarti (the former only is required for regulatory import testing of animals into WA). Number of eggs/oocysts/g faeces only provided on request.

Other laboratories using this method for testing animals entering or having already entered into WA as per import requirements are required to state on their laboratory report that this DPIRD method has been adhered to.

12. Notes

The presence or absence of Fasciola hepatica is a significant finding because WA is free of liver fluke infection. For this reason the results are reported as positive and negative only. The presence of other trematode eggs or of oocysts of Eimeria leuckarti is, in most instances, without clinical significance, but is reported or referred to in the ‘Comments’ section.

13. Glossary of terms

14. References

4450 Benedek L (1943). Untersuchungen auf Leberegeleier durch Sedimentation. Allatorv. Lap. 66: 139–141.

4247 Boray JC (1969). Experimental fascioliasis in Australia. Adv. Parasit. 7: 95–210.

4246 Boray JC and Pearson IG (1960). The anthelmintic efficiency of tetrachlorodifluoroethane in sheep infested with Fasciola hepatica. Australian Veterinary Journal 36: 331–337.

1986 Happich FA and Boray JC (1969). Quantitative diagnosis of chronic fasciolosis. Comparative studies on quantitative faecal examination for chronic Fasciola hepatica infection in sheep. Australian Veterinary Journal 45: 326–328.

4451 Knapp SE and Presidente MS (1971). Efficacy of Rafoxanide against natural Fasciola hepatica infections in cattle. American Journal of Veterinary Research 32 1289–1291.

3887 Rapsch C et al. (2006). Estimating the true prevalence of Fasciola hepatica in cattle slaughtered in Switzerland in the absence of an absolute diagnostic test. International Journal of Parasitology 36: 1153–1158.

Contact information

Terry Miller