Abstract

Haemonchosis is a common parasitic disease causing significant morbidity and mortality in ruminants. Antiparasitic drugs have been employed to control Haemonchus contortus and H. placei infections but parasite resistance to anthelmintics remains a significant concern.^3,5 Alternative strategies to control abomasal parasites have been proposed and include using copper oxide wire particles (COWP) and feeding tannin-rich forage such as sericea lespedeza.^3,4,6 Diatomaceous earth (DE) can be an effective treatment to control intestinal parasites in free-range layer hens.¹ However, there is a lack of scientific evidence to support its use in ruminants.² DE is the fossilized remains of diatom shells ground into a fine mineral-rich dust. The abrasive properties of this dust are thought to traumatize the cuticle of invertebrates leading to their dehydration and death. An advantage of DE over COWP is that DE should be effective against parasites throughout the gastrointestinal tract. COWP are only effective against abomasal worms. A 16-day pilot study was initiated during which Sudan Barbary sheep (Ammotragus lervia, n=16) were fed DE to assess effectiveness in reducing fecal egg counts. One pound of DE was mixed with 40 pounds of a pelleted ration using Karo syrup as a binder and fed as lib. Blood and fecal samples were obtained pre- and post-treatment. Nine out of the 16 individuals showed a lower egg count post-treatment. A comparative study was done using a control group to prove statistical value. Additional studies are needed to determine effective strategies for the use of DE in ruminants.

Acknowledgments

The authors thank the San Diego Zoo Safari Park veterinarians, veterinary technicians, laboratory technicians, nutritionists, and keepers for their assistance with this project.

Literature Cited

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