Raise your hand if you’ve ever randomly selected a dewormer from the shelves of your local tack store without doing any research first? Come on, be honest. We’ve all done it, right? I’ll soften the blow for you and be the first one to say that I usually chose a dewormer based solely on my bad memory from the previous purchase nine weeks before. If I had to guess, so have you!
Did you know that the rotational dewormer method most horse owners still use was actually developed back in the 1960s? And it was based on a drug that is no longer even available? Thiabendazole, to be exact. Thiabendazole was originally intended for the prevention of large strongyles and verminous arteritis colic, but according to Dr. Hoyt Cheramie, DVM, MS, manager of Equine Veterinary Service, for Merial, these large strongyles “have virtually been eradicated on most well-managed horse farms.”
This was eye-opening information to me! So, why are we stuck in a 60-year-old method?
Here’s another candid confession: before I started this post series, I did NOT want to change my current method because I thought A.) The newer fecal egg count, or FEC, method I’d heard about was just another way for veterinarians to make money B.) FECs were a ploy for the big pharmaceutical companies to get me to buy more dewormer C.) I don’t have the time or extra money to make appointments just so someone can sort through my geldings’ poop and D.) My horses seemed healthy enough not to change my current method.
But this new information intrigued me, and made me wonder if I was doing a disservice to my own personal horses and perhaps even to my boarding farm. So I dug deeper. Dr. Hoyt Cheramie graciously provided me with loads of information and even completed an interview for me, including questions from real-life horse owners, some from my own boarding barn. After reading through all his helpful information, I’m forced to discredit all my previous assumptions about the new and improved fecal egg count deworming method.
Why you should stop using the rotational deworming method:
Besides the previously-stated fact that the old rotational method was intended for a drug no longer on the market, parasites have started to display resistant properties. Specifically, “there is significant known resistance to fenbendazole, oxibendazole, and pyrantel in the United States,” says Cheramie. Selective deworming, as opposed to calendar-based rotation, targets the specific needs for individual horses better than a broad approach.
What exactly a FEC does:
Fecal egg counts identify all types of parasite eggs. However, the test can only count the number of strongyle-type eggs. Tapeworms are usually not found in fecal egg counts. FEC tests will help categorize your horse as a “low” or “high” shedder, thus guiding your veterinarian in the number of treatments needed each year. Low shedders might only require one or two treatments per year, whereas high shedders need closer to four or five.
How to start a selective deworming program with your own horses:
The first step is to run a fecal egg count on your horse. Your veterinarian will help you evaluate the results and give guidance on which drug would be suitable for your horse. According to Dr. Cheramie, you should have an FEC done twice in the first year–once right before treatment, and once after treatment to get an “accurate characterization of shedding potential.” The FEC will also show you if the drug your vet helped you choose did its job. Once you categorize your horse as a low or high shedder, you can have a fecal egg count performed about every two years to test your treatment and shedding level.
After reading various scientific-based articles and the interview completed with Dr. Cheramie, here are the key points I took away from this study:
1. The rotational deworming method horse owners commonly use encourages over-treatment and parasite resistance. FECs, on the other hand, can help lower the number of treatments per year and treat more specifically.
2. FECs can potentially lower the number of deworming treatments for your horse–and save you money!
3. FECs will help categorize your horse as a “low” or “high” shedder, which will guide the number of treatments for your horse.
4. After the initial year in which you begin selective deworming, you only need to do an FEC about every two years to check your treatment regimen.
I ran across a few recurring special cases while questioning fellow horse owners that I asked Dr. Cheramie to shed some light on.
The Weekend Warrior
I’m an avid trail rider, gone most weekends in the summer months, and I’m worried about my horse living around other horses who might not be treated for parasites. Should I deworm more frequently during these months to protect him?
Nope! Short periods of exposure to different horses and their parasites will not increase your horse’s health risk! In fact, Dr. Cheramie says that “a possible benefit is he’ll get exposed to susceptible parasites (rather than resistant parasites) and bring those parasites back to the farm, which may help combat resistance.” Stick with your fecal egg count-based plan that you create with your veterinarian.
The Small Acreage Equestrian
I only own two horses and keep them on about 10 acres at my home. They seldom travel or see other horses. Do they need to be dewormed as often as say, boarded horses?
Parasites will still be on your property, and depending on your horses’ immunity and the grazing density, the exposure to parasites may be low or high. Fecal egg counts should still be conducted to determine your herd’s shedding patterns. If they’re low shedders, they might only need to be treated one to two times per year. But it’s best to run the tests to make sure so you don’t over-treat or use the wrong drug.
Chemicals are so harsh. I prefer to use all-natural methods. Are there any natural parasite remedies?
Unfortunately, no. The good news is, Dr. Cheramie says “using selective deworming along with understanding local climate/parasite ecology will allow us to limit how often we deworm.”
After researching this newer, more effective method for deworming, I cannot deny the science behind it. Not only that, it will save me time AND money! To satisfy my inner skeptic (and yours), I’m going to run FECs on all three of my geldings. I hope you follow me on my journey– and I promise I’ll hold nothing back. You’ll get to see how I take my poo samples, where I take them, and how much it cost, the results, as well as my new deworming plans. Be sure to subscribe to my email list so you don’t miss it!
I want to give a special thanks to Caleigh Williams from Merial for hooking me up with some awesome information! And thank you, Dr. Hoyt Cheramie, for extending your expertise to my little horsey blogging world!