Parasite Infections Increase in Warm Weather

Newsdate: Fri, 6 May 2011 - 07:29 am
Location: MADISON, New Jersey

As the weather heats up so does the risk of parasite infections in horses. Horse owners want their horse’s to look and feel their best. However, with concerns of efficacy and resistance on the minds of horse owners and veterinarians, many are asking what should they deworm with this season?

“Now is the best time to work with a veterinarian on a deworming strategy,” said Dr. Lenz. “Deworming every 6-8 weeks whether horse owners rotate dewormers or use the same dewormer is no longer the answer. It is important that each horse is getting the dewormer that is most effective against fighting parasite infections for them.

A veterinarian designed 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.

QUEST and QUEST Plus control a broad spectrum of parasites, including large and small strongyles (including the encysted form of small strongyles, cyathostomes), ascarids, pinworms, hairworms and bots. QUEST Plus also effectively controls tapeworms (A. perfoliatum). 90 percent of parasites come from the environment that the horse is exposed to every day.

Even without creating clinical signs, migrating parasites can damage vital organs and rob the horse’s health. Including QUEST or QUEST Plus in a 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 intestine1. Unlike large strongyles, the small strongyle (cyathostomes) larvae do not migrate beyond the wall of the intestines1. However, they burrow in or encyst in the wall of the large colon producing inflammation that may lead to diarrhea1. Once larvae become encysted they are resistant to most dewormers.

The unique active ingredient in QUEST and QUEST Plus controls encysted small strongyles in just one dose. The clear gel formula is absorbed and begins working immediately to break the pattern of infection by interrupting the parasite life cycle and reduce 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 deworming program this spring, it is important to consult with a veterinarian on the risk of parasite infection for each individual horse.”

Knowing the unique conditions that affect each horses parasite risk is important to any deworming strategy. Some 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.

Timing when to deworm with QUEST and QUEST Plus depends on the region where the horse is located and if they are 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 deworming products. Generally, QUEST or QUEST Plus should be administered in the spring and again in the fall.

Extreme caution should be used when administering QUEST and QUEST PLUS to foals, young and miniature horses, as over dosage may result in serious adverse reactions. Do not use in sick, debilitated or underweight animals. These products should not be used in other animal species, as severe adverse reactions, including fatalities in dogs, may result.

About the Author

Flossie Sellers

As an animal lover since childhood, Flossie was delighted when Mark, the CEO and developer of EquiMed asked her to join his team of contributors.

She enrolled in My Horse University at Michigan State and completed a number of courses in everything related to horse health, nutrition, diseases and conditions, medications, hoof and dental care, barn safety, and first aid.

Staying  up-to-date on the latest developments in horse care and equine health is now a habit, and she enjoys sharing a wealth of information with horse owners everywhere..