Readers Like to See Proof for Rotational Deworming

More than 800 readers of responded to a poll asking, "What would make you stop using a rotational deworming program?"

results of poll on rotational deworming

Results were as follows: 

  • Proof that it isn't necessary/working on my farm: 42.31% (341)
  • A recommendation from my vet: 24.94% (201)
  • Nothing, I think rotating dewormers is best for my horse: 13.77% (111)
  • I don't currently rotate dewormers: 12.53% (101)
  • Other: 6.45% (52)

Readers shared what their thoughts on rotational deworming in the comments below.

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Poll sponsored by Merial.

  • Daily wormer and biannual ivermectin
  • fecal counts that don't indicate the need for rotation or worming.
  • I use Strongid C2X with twice a year Equimax.
  • I usually target a specific parasite and choose the de-wormer which I think works best for that para
  • I rotate pastures, so I worm when moving them as not to carry along new pests to the new area.
  • I use a daily wormer plus spring and fall using Quest or IV Gold
  • use the daily wormer and 2x a year ivermectrin per vet
  • My understanding is that ivermectin is all that is needed for worming my horse.
  • I use Quest/Quest Plus
  • Our horses are on daily wormer per our vets suggestions, and paste every 6 months - great results!
  • being able to afford/having access to regular fecal exams
  • Ivermectic resistance means fecal floats and worm when needed
  • We use a fecal testing basis for determining which horses should be wormed and with which product.
  • when fecal exams show it is not necessary
  • A decent stool testing program, that will identify worms and wormer to use.
  • I had fecal egg counts done
  • A recommendation from my vet, and proof it isn't working. my
  • use peer-reviewed articles to make decisions.
  • Don't rotate, never have. It's not necessary and is more likely to lead to resistance.
  • I have always used rotational dewormers and have never had a problem.
  • Per my vet, every year I alternate daily & rotational program
  • No worms detected after doing fecal samples
  • My horses have a lot of acreage to roam on, so I worm infrequently 1 or 2 x per year
  • scientific evidence that offered something better
  • used to be on daily strongid and it is not recommended because of resistance
  • My vet would have to prove to me that rotating dewormers wasn't working before I would stop.
  • I rarely rotated when I wormed. I used Ivermectin. It's been over 1 year of NEG fecal counts.
  • I use quest & quest plus all year
  • I do FEC
  • Free fecal checks by a vet to indicate presence/type of parasite and recommend appropriate wormer.
  • through fecals that the count was low
  • ivermectin year round does the trick
  • If they came up with a dewormer that kills everything, every time.
  • we have just started doing fecals and treating as needed.
  • worm spring & fall - test feces Feb. & Oct. adjust as needed
  • Education and proof of a realistic and better way
  • A product given that kills all worms.
  • An alternative that works just the same or even better
  • i treat for worms my horses test positive for.
  • i would stop if it was encouraging worm resistance
  • A large long study proving it doesn't work.
  • I do fecal tests first and then if nesessarem worm with the approprieate wormer
  • Discussion with vet with proof, and proof via testing that it isn't necessary.
  • I use a daily wormer
  • only use dewormer when fecal count dictates needed
  • fecal counts
  • Recent equine hospital exam indicates it is working-for us. If vet recommended change would consider
  • New AAEP guidelines that are easy to follow for the owner
  • It costs twice as much to get a fecal check then buy a tube of wormer. Most can't afford that now.
  • A less expensive fecal egg count test.
  • I have already decided to stop. Going to fecal testing and targeting what's needed
  • After 2 out of 3 horses showed low/no egg count, I stopped rotational deworming.
  • In FL I give mostly ivermec based wormers, but will do PowerPak w/ Safeguard 1x/yr.
  • being on a farm that does a better job of manure disposal.
  • test manure-treat only what is present.
  • education on how to easily do fecal counts on the farm without vet charges
  • I do rotation and it has worked for me several years
  • Few horses so rely on fecals, but will rotate as needed.
  • I don't particularly like ivermectin
  • My colicky gelding is on a daily wormer; the rest follow AAEP's schedule. This is my vet's advice.
  • I target the bug of the season per the vet
  • Rotation is not the way. Too much science pointing towards resistance!!
  • I have used in my oldr horses their whole lives and they lived to be 27 and 29. As a wormer is prove
  • We asked our vet about this, and he continues to recommend rotational deworming.
  • Any developed treatment that is 100% foolproof!!!
  • could find a natural product, not harsh chemicals
  • I only change wormers when egg counts go up or to target one kind of worm
  • Fecal egg counts! Have already stopped worming unless necessary!
  • the life cycle of a parasite dictates rotation fo de-wormers is the only thing that would work.
  • and...really, really CHEAP "home" fecal test kits...come on scientists!
  • Only if it was detrimental to the health of my horses.
  • I might change if a new product came out that is not yet resisted by the worms.
  • I use DE (fossil shell flour) for parasite control. documentated cases that it works
  • do fecal exams
  • I do fecal test and deworm as to the results
  • if proved not to work
  • A proven dewormer that gets ALL worms w/no resistance to the medication.
  • We do not deworm on schedule at the moment - do fecals to determine what type of shedder horse first
  • stopped rotations 7 yrs ag on vet's recommendation - use Equimax every 60 days
  • easy way to get fecal egg count
  • cheap easy fecal's
  • as a veterinary technician though, it would have to be irrefutable proof.
  • Don't want to give my horses anything that is unnecessary.
  • I deworm when necessary. Use fecal samples.
  • fecal testing
  • I have seen too many dewormers claim no rotation and fail
  • I don't use wormers. I remove droppings and have samples analysed for wor
  • I do a fecal count and deworm as my vet recommends. Haven't needed to over a year!
  • routine fecal egg counts to determine parasite type and load to target worming of individual horses
  • I don't rotate my dewormers, I do fecals then decide what dewormer they need and recheck them again
  • I would prefer to use fecal egg counts to determine when to deworm
  • I have fecal checks done then follow my vets recommendation.
  • We have changed our program and double up on complimentary wormers plus 1Xyear Power Pac
  • SCIENTIFIC PROOF that it isn't necessary & an all-in-one wormer really exists!
  • i do fecal egg counts & treat accordingly
  • total resistance
  • My vet recently recoomended just that. We now do fecal testing quarterly and deworm for tape and bot
  • My vet offers fecal sampling for a low price. If there are worms, wormers are free!
  • i use ivermectrin
  • None of the answers fit for targeted deworming.
  • Wish would stop sponsering specific advertizers with this type of question
  • I would need proof that it's not working, but it would need to come from my vet, after tests.
  • but only when it is necessary thus using the fecal egg count method
  • Strategic deworming based on FECs, treat for tapes in Spring and encysted sm Strongyles in fall

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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