Evidence-based Deworming Strategy.



Most of the parasite eggs seen on a fecal exam come from one of many small strongyle species–collectively known as cyathostomins. Cyathostomins are ubiquitous parasites of grazing horses, and are currently considered one the most significant pathogenic internal parasites in horses. Drug-resistance among small strongyles has been intensely documented throughout the last decade. In addition to small strongyles, Parascaris Equorum, commonly known as roundworm, or ascarids, also constitute a major threat to equine health.

Unlike small strongyles, ascarids are found most commonly in foals and younger horses. Adult horses usually have low numbers due to the development of immunity during the course of infection. However, it is important to note that the reduced efficacy of anthelmintics and development of multiple drug-resistance to equine ascarids has been reported in many countries, including the United States.

“The traditional one-size-fits-all treatment approach, dictated by the calendar alone, is not only inadequate but actually a recipe for disaster. Instead, the best method of parasite control requires a two-step process, implemented on a farm-by-farm and horse-by-horse basis. First, evidence must be collected to determine which dewormers still work in a particular herd and which have been rendered ineffective due to resistance. Then, the specific horses in need of deworming must be identified and a schedule for the administration of a targeted anthelmintics devised.” ~ Craig Reinemeyer, DVM, PhD.

“I’ll hear people say that deworming is cheaper than a fecal egg count. But if you’re deworming with a product that no longer works on your farm, it’s just wasted money. Do that once or twice a year and it becomes more expensive than a single egg count.” ~ Dr. Ray Kaplan, DVM, PhD.

“I never felt right treating something I couldn’t see, and I always suspected my horses didn’t need to be wormed as often as recommended. Now I have my own FEC lab and Eggzamin has helped me learn to do the test and  identify parasites. I can test my horses to determine if they need treatment, and I am finding that they need it much less frequently!”   

~ Lee Posey, Oregon