There is a lot of information out there about which dewormer to use, which to stay away from or whether to deworm at all. Would a ‘natural’ dewormer such as diatomaceous earth do as well? Is natural better? I recall from wildlife medicine that the main disease problem of wildlife is parasitism. Do we want that for our fourlegged friends by going ‘natural’. Predation is also natural and I doubt anyone would accept that fate for their horse. Worms can and do cause serious, even fatal disease in horses.