Equine News
The finest care for your horse in Maine.
De-worming: Rethinking Parasite Control
Parasite resistance to the drugs we most commonly use is becoming an increasing concern in our horse populations. For many years veterinarians and horse owners have been using rotational de-worming to combat parasites. This aggressive de-worming protocol may now be contributing to the development of resistant parasites. This could eventually lead to a devastating parasite problem: in the not so distant future we could be faced with a parasite population that does not respond to ANY of the drugs currently available. If this occurs, we would essentially be back at square one with parasite control (think 1970s!) Prior to effective parasite control, horses were plagued with unthriftiness, plus a marked increase of colic incidence and premature death.
In an effort to reduce the development of resistance to de-worming drugs, Equine Veterinary Service would like to adopt a new strategy for combating parasites in our horse populations. It is IMPERATIVE that you, our clients, help us maintain the effectiveness of the currently available de-worming drugs by participating. Using published, evidence-based research we are in the process of changing our de-worming recommendations.
Our goal with de-worming from now on will be to de-worm only as needed based upon the results of quantitative fecal exams. These tests provide much more information than a routine fecal used for basic screening. The quantitative fecal exam actually provides the number of parasite eggs per gram of feces that exist in an individual horse. We will use these numbers to determine the ideal de-worming strategy for individual horses and barns.
Just like certain people are more susceptible to colds and flu, certain horses carry a much higher parasite load than others. In fact, research has shown that 20% of the horse population harbors 80% of the parasite burden. Clearly, as these horses are the ones contaminating the environment, they are the ones that need to be de-wormed most regularly. This does NOT mean that we stop treating other horses, however. It is important to continue a modified de-worming program for all horses, with the horses with the highest worm burdens being medicated most frequently.
What does this mean for you now? When either Dr. Judd or Dr. Solomon visits your farm this spring, we will recommend testing all horses’ manure with a quantitative fecal test using the McMaster Method. Once these results come in, we will help begin to design a program for your horse(s) and the environment they live in. While this program certainly involves more effort, we feel that it is exceedingly important to begin to tackle the increasing problem of parasite resistance. We hope you will participate and we are happy to discuss any questions/concerns that arise!