Parasite control & grazing systems for horses: The Southern-European perspective

Take home message

About parasitism

Parasitism is based on a continuum equilibrium among hosts, parasites and environment

• It is considered 9 out of 10 parasitic form (oocyst, egg, larvae, adult) are in the environment

Pasture is contaminated by few animals

• Approx. 20% animals tend to burden 80% of parasites
• They are considered high egg shedders, should be identified

Southern European regions have climatic conditions characterized by high temperatures and low pluviosity, that impairs internal parasite development and survival and enhance ectoparasites and related diseases

• Horses are rarely indoors, they pasture all year long
• Major internal parasites in grazing animals are species of Gasterophilus (mainly G.intestinalis), strongylines (even Strongylus vulgaris), ciathostomines, tapeworms (A.perfoliata and A.magna) and ascarids (Parascaris univalens as well), while indoors animals also harbour Oxyuris equi and coccidia. Infection by hepatic trematodes such as Fasciola o Dicrocoelium can also be detected.
• Major external parasites are ticks and flies and agents of Vector Borne Diseases as piroplasms or tripanosomatids; Habronema/Draschia species and Setaria can be also seen.

About control parasite strategies

Horse health and welfare are focused on high value animals, as well as breeding farms (individual medicine vs population medicine)

• Horse parasite control needs a “Taylor made” deworming program
• Faecal sample analyses are needed

To build up a sustainable and health care deworming management

• Know which worm species should be controlled
• Keep fields and stables as clean as possible
• Animal age, hygiene and management must be considered in any strategy

References

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