Warm Weather Horse Deworming Strategies

Parasites love warm weather just as much as we do and spring and summer are a good time to evaluate your horse deworming program.But what worming program for horses is best? With concerns of efficacy and resistance on the minds of horse owners and veterin

Parasites love warm weather just as much as we do, and summer is a good times to evaluate your horse deworming program.

Summer is a good time to remember to deworm your horse.

But what worming program for horses is best? With concerns of efficacy and resistance on the minds of horse owners and veterinarians, many horse owners are asking what should they use for horse deworming this season? A veterinarian designed equine deworming program including QUEST® (moxidectin) and QUEST® Plus (moxidectin/praziquantel) is a key step to protecting against the health problems that come from dangerous parasites, Pfizer experts say.

QUEST and QUEST Plus control a broad spectrum of parasites, including large and small strongyles (including the encysted form of small strongyles or cyathostomes), ascarids, pinworms, hairworms and bots. These are all important challenges when deworming horses. QUEST Plus also effectively controls tapeworms (A. perfoliatum), an important part of horse dewormer rotation.

About 90% of parasites come from the environment that the horse is exposed to every day, making horse dewormer rotation important. Even without creating clinical signs, migrating parasites can damage vital organs and rob the horse’s health. Including QUEST or QUEST Plus in a horse deworming program can control parasites that decrease nutrient absorption, lead to colic or pneumonia, cause irreversible lung damage, impair performance, stunt growth, cause weight loss and impair coat condition.

Of all the equine parasites, small strongyles (cyanthostomes) are considered by equine pathologists as the most dangerous. The adult forms of both large and small strongyles live in the large intestine. Unlike large strongyles, the small strongyle (cyathostomes) larvae do not migrate beyond the wall of the intestines. However, they burrow in or encyst in the wall of the large colon, producing inflammation that may lead to diarrhea.

To learn more about deworming, download our FREE guide—Deworming Your Horse: How to find the best deworming schedule for you and your horse.

Once larvae become encysted they are resistant to most equine deworming strategies. However, the unique active ingredient in QUEST and QUEST Plus controls encysted small strongyles in just one horse deworming dose. The clear gel formula is absorbed and begins working immediately to break the pattern of infection by interrupting the parasite life cycle and reducing strongyle eggs from contaminating pastures where horses graze. QUEST and QUEST Plus are the only products FDA-approved to suppress production of small strongyles eggs for up to 84 days.

“QUEST and QUEST Plus has been proven safe for numerous breeds of horses and ponies, as well as in breeding mares and stallions and foals six months of age or older,” said Tom Lenz, DVM, MS, Diplomate ACT and Senior Director, Equine Veterinary Services for Pfizer Animal Health. Before beginning any horse deworming program, it is important to consult with a veterinarian on the risk of parasite infection for each individual horse, Lenz said.

Knowing the unique conditions that affect each horses parasite risk is important to any horse deworming strategy. Some equine deworming factors to consider include age of the horse, local climate cycle, manure removal, pasture rotation, types of pastures, use of the horse and how the horse is fed. For a complete checklist of parasite risk factors, visit www.IDMyHorse.com.

The timing of a worming program for horses with QUEST and QUEST Plus depends on the region where the horse is located and if the horse is at low, medium or high risk to parasite infections. Low, medium and high risk are based on a fecal egg count (FEC), which is performed by a veterinarian. Less than 200 eggs per gram may indicate a low risk, while greater than 500 eggs per gram may indicate a horse is a higher risk of spreading infection.

Every horse is different, so it is important to work with a veterinarian to determine appropriate seasonality and duration for all horse deworming products. Generally, QUEST or QUEST Plus should be administered in the spring and again in the fall. For an equine deworming recommendation schedule, visit www.IDMyHorse.com.

Ride in health,


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