Poll: Readers Look for Proof Against Rotational Deworming

More than 840 readers of TheHorse.com responded to a poll asking, "What would make you stop using a rotational deworming program?"

results of poll on ulcers

Results were as follows:

  • Proof that it isn't necessary/working on my farm: 42.45%
  • A recommendation from my vet: 29.63%
  • I don't currently rotate dewormers: 17.05%
  • Nothing, I think rotating dewormers is best for my horse: 10.87%

Readers share their theories on rotational deworming in the comments below.

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  • Proof would have to stand up to repeated testing.
  • I use diatomaceous earth, haven't used a commercial wormer in 16 years.
  • I use a daily wormer plus spring and fall treatments with Ivemectin or Quest have never had a colic
  • we deworm 2 times a year
  • I agree we have to change our ways and catch up to the 21st century for the good of our horses.
  • do fecal test
  • No such thing as 'proof' but good evidence to do something alternative would be needed before change
  • I will continue my horse's rotation program, as I feel it does help him.
  • Proof that it's not necessary via fecal count every so often, which would determine....worm or not.
  • only worm when fecal shows high egg count
  • My horses' fecal tests are normal. Equimax give in Dec. for tapes.
  • Vet has just changed us to "test" and worm if needed based on results.
  • accurate fec from my vet every 3 months
  • I have changed to using fecal samples to determine deworming
  • A fecal egg count shows what's really there, as opposed to what we worms think are there.
  • reasonable cost and easy way to do test
  • Itave already stopped and am doing fecal counts
  • i get fecal worm egg counts done twice yearly
  • I use the vet-recommended dewormer as needed based on FEC tests
  • I do worm egg counts, which show normally 0, and give Equimax in November for tape worm.
  • Our barn owner dictates who gets what, and when. She's the only barn, in our area, with NO parasites!
  • Availability of easy tests would help
  • I try to keep up with new info and have routine discussions with my vet about best/latest ideas.
  • Using fecal egg counts to determine schedule.
  • i have been doing FEC for a year & LOVE the fact my horse does not get chemicals she doesn't need
  • we only worm if fecal tests shows it's necessary
  • I actually stopped this year/ Had a fecal done and my horse had no eggs.
  • Only deworm 2-3 times a year anyway
  • it's already been proven that rotational deworming is out of date!
  • i use a daily wormer.
  • I do fecals on my own horses and worm them as needed
  • I do a fecal count twice a year and then use whatever the vet recommends.
  • If fecals were not so expensive for several horses
  • its worked for over 30 years for me "why change"
  • I use targeted de-worming with egg counts
  • I do a fecal egg count, then rely on vet's recommendation.
  • I do fecal worm testing before deworming and then determine from the results which dewormer to use.
  • Fecal testing then use the right product.
  • I worm in the spring and then do stool collections to take to the vet for egg counts.
  • Have not rotated for many years--resistance in SE makes it useless
  • N.O.M.S. powder works GREAT!
  • most do not work anymore
  • Sheep industry learned what happens w/routine deworming-resistance to all products.
  • Stopped for a year. Used only Quest Plus. Fecal exam after 1 yr on 7 horses, 0 parasites.
  • "closed" herd, fecal exams show minimal infestation, deworm only as necessary
  • Without the OK from my vet, i would not stop my current worming program.
  • I use feed-thru wormer and have never had a problem in 10+ yrs
  • I have stool samples checked and then worm accordingly. There is really no fool proof method
  • Some I rotate and some I don't. Depends on the horse.
  • have tried rotations and when not using zimectrin gold my horses got pin worms
  • if the vet says switch, I will
  • I do an annual fecal exam with my vet to determine what deworming is required.
  • Too much info showing rotational deworming is no longer valid. We use Pfizer's Horse ID program
  • I only worm when the fecal exams indicate it's necessary; then I know what type of worm to eradicate
  • Cheap do it yourself fecal tests
  • I rotate thinking i should. but what about daily deworming products? Is this system better?
  • Due to the resistance issues I now have a fecal run every 8 weeks and deworm based on that.
  • Two times per year deworming not necesery to rotate
  • Something that works one time a year on all worms
  • I do fecal exams every three months and worm for the specific worms present.
  • Scientifically proof that rotational worming is a waste of money...
  • The price of taking a fecal sample analyized will stop most people from checking it.
  • Not every parasite dies with iver, and even with it resistance cd someday develop. Rotation is safer
  • ROTATION IS RECOMMENDED BY VETS IN THE SW.
  • Testing fecal count just gives vets another way to makemore $ with the number of times it needs to b
  • Will rotate unless vet says not to. Dang those nasty things.
  • I use a daily dewormer
  • I have my horses on a daily wormer and treat them with Equimax twice a year.
  • my vet having equipment to test feces
  • Fecal exams that are cheaper than dewormers
  • I use fecals and have been told by my vet NOT to rotate.
  • Seems to me this is such old news. I'm amazed that anyone continues to rotate wormers.
  • problem is, fecals do not tell the whole story so it's impossible to know the actual count
  • I weighed advice from vet to limit worming and not work regular every 3-4 months & no need to rotate
  • using FEC and per vet recommendation have tailored a dewoming program for our farm
  • I do fecal egg counts twice a year, 3 equines, zero eggs,treat for tapeworms spring & fall.
  • I worm ONLY when needed and have very shiny, healthy horses!
  • we only worm based on need from fecal checks 4x/year
  • We do Fecal Egg Counts periodically.
  • Based on an educational seminar I attended, I now only work according to fecal count requirements
  • I still rotate, but according to season and the priminant concern of that season.
  • I deworm based off of FEC results.
  • If "natural" product could be offered, I would jump on it. Parasites have evolved w/horses
  • I currently use fecal test results to determine my worming needs.
  • I would need to have proof.
  • I check fecals
  • I rotated at one time, but when my horses still showed signs of worms I switched to a daily dewormer
  • The farm I board at does Ivermectin every 2 mo. except in Jan when we use Zimectrin Gold
  • I want to stop but can't convince the barn owner who firmly believes in it!!
  • however - I only deworm 3x per year
  • I understand science is advancing, but my horse is healthy on a rotation.

About the Author

Megan Arszman

Megan Arszman received a Bachelor of Science In print journalism and equine science from Murray State University in Murray, Ky., and loves combining her love of horses, photography, and writing. In her “free time,” when she’s not busy working as a horse show secretary or riding her American Quarter Horses on her parents’ Indiana farm, she’s training and competing her Pembroke Welsh Corgi and Swedish Vallhund in dog agility and running.

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