Diatomaceous Earth as an alternative treatment for internal parasitesTuesday, 8th June 2021
By Dr Mackie Hobson
DIATOMACEOUS EARTH as an alternative treatment for internal parasites
Mohair producers often ask is Diatomaceous earth (DE), also known as Diatomite, an effective in treatment for internal parasites in Angora goats.
To answer the question we look at trials conducted by Nkwanda, Hoon and Fourie at the Grootfontein Agricultural Development Institute on the impact it had on lambs.
What is Diatomaceous earth (DE) also called Diatomite?
DE is a naturally occurring, silicon-rich sedimentary rock made up of fossilised remains of millions of diatoms, a type of hard-shelled plant algae originally deposited millions of years ago in the earth from dried up seas and lakes
How is DE supposed to work as an anthelmintic?
One theory states that because DE has small, sharp edges, its abrasive action scratches off the waterproof coating of the insects and absorbs lipids from the waxy outer layer of their exoskeletons, causing them to dehydrate and die. Another theory is that DE acts as a buffer in the stomach, thereby creating an unsuitable environment for the feeding and reproduction of the parasites (Köster, 2010).
The mineral contribution of DE might also play a role in improved production, as it contains a broad spectrum of naturally occurring minerals. The properties that DE possesses in improving the absorption of other minerals, in particular the effect of silicon on improved overall mineralisation (e.g. bone), could furthermore be a possible reason for enhanced animal performance (Köster, 2010).
What other studies have concluded about DE is a treatment for parasites?
- McLean et al. (2005) reported that cattle and sheep that received a DE supplement had low faecal egg count (FEC) for the duration of the experimental period was similar to animals teated with an anthelmintic.
However other studies suggest it is not a beneficial treatment
- In a study with goats by Gregory et al (2009), DE did not show any significant effects on the parasite
- In a study by Osweiler & Carson (1997) with grazing lambs fed DE at 5 and 10% of a supplemental ration, no significant difference in FEC and abomasal gastro-intestinal larval counts were found in control vs. DE-fed lambs.
- In a review article, Whitley & Miller (2015) concluded that the majority of controlled studies with published results including sheep, goats and cattle, have noted no significant impact of DE products on gastrointestinal nematode infection indicators.
What did the Grootfontein study conclude?
The Grootfontein trial on lambs involved DE in their diets at different levels: 0.5%, 1%, 1.5%, and 2.0% as well as a control group of 10 lambs each.
The Grootfontein study of DE at levels up to 2.0% in feedlot diets DID NOT significantly reduce parasite loads as measured by FEC. (Coccidiosis and Roundworm counts).
Out of interest the inclusion of different levels (0.5 to 2.0%) of DE in feedlot diets did not have a significant effect on the growth rate, carcass characteristics or FEC of lambs in this study.
THE EFFECT OF DIFFERENT INCLUSION LEVELS OF DIATOMACEOUS EARTH IN FEEDLOT DIETS ON THE PERFORMANCE OF LAMBS A.T. Nkwana1,2, J.H. Hoon1# & P.J. Fourie2 1 Grootfontein Agricultural Development Institute, Private Bag X529, Middelburg (EC), 5900 2 Department of Agriculture, Central University of Technology, Private Bag X20539, Bloemfontein, 9300
Köster, H., 2010. Diatomite in animal feeds. Animate Animal Health.
McLean, B., Frost, D., Evans, E., Clarke, A. & Griffiths, B., 2005. The inclusion of diatomaceous earth in the diet of grazing ruminants and its effect on gastrointestinal parasite burdens. In: International Scientific Conference on Organic Agriculture, Adelaide, Australia, 277-280.,
Gregory, B., Mulumebet, W. & Mohamed, A., 2009. The effects of diatomaceous earth on parasite infected goats. Bull. Georg. Natl. Acad. Sci. (3)1, 129-135.
Osweiler, G.D. & Carson, T.L., 1997. Evaluation of diatomaceous earth as an adjunct to sheep parasite control in organic farming. Leopold Center Completed Grant Reports, 102. http://lib.dr.iastate.edu/leopold_grantreports/102.