US stud in fly product wrangle

A stud and training centre in California has been awarded more than US$1m after a jury found that a fly control product used by the stud was defectively designed and had caused harm to its horses.

Charlotte and Christopher Wrather, owners of the Thoroughbred and warmblood Cottonwood Ranch, and stud manager Lori Araki claimed that “feed-through” fly control product Equitrol, made by Farnham Horse Products, caused or exacerbated health problems in their horses, including reproductive problems, birth and growth defects, neurological dysfunctions, low thyroid and diarrhoea.

Equitrol, which has been on the market for more than 20 years in the US and is registered with the US Environmental Protection Agency (EPA), works by killing fly larvae before they mature, thus preventing the development of flies in manure. The California fly season is from March to early November, and the product is fed in pellet form.

The active ingredient in Equitrol is an organophosphate insecticide called tetrachlorvinphos, which is also widely used in other products in the US. To Horse & Hound’s knowledge, there is no similar feed additive in this country. Over-the-counter fly repellents normally contain permethrin or are citronella-based.

Farnam is to appeal the verdict. Chris Jacobi, president of Farnam Horse Products, says: “Its safety is reflected by its long-standing tenure in the marketplace. All our products undergo extensive testing before they become available to consumers.”

Read the full story in the current issue of Horse & Hound (15 April).

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