Poop! So Eggciting!

By Patty Wilber

If you take horse poop and mix it with sugar water, you can get eggs from the horse’s parasitic worms to float!

Oh that does sound yummy doesn’t it?

I have done my share of fecal floats–more than 2000 of them when looking at the effects of parasites on ground squirrel populations in Idaho.

But I have never floated my horse manure…


Not all horses (or squirrels) are created equal in the worm infestation world.

Some horses have immune systems that preclude massive infection.  If every two months is unnecessary for your horse, why throw money down her  gullet (in the form of wormer) if you don’t need to?

And scarier: indiscriminate use of antihelminthics is leading to the evolution of resistant worms–and the USA may be the place with the highest levels of resistance.

Kaplan, 2004 performed FECRTs on 1274 horses at 44 large stables in Georgia, South Carolina, Florida, Kentucky, and Louisiana. Four different dewormers were evaluated on each farm: fenbendazole, oxibendazole, pyrantel pamoate and ivermectin.

The percent of farms found to harbor resistant worms were as follows: 97.7% for fenbendazole, 0%, for ivermectin, 53.5% for oxibendazole and 40.5% for pyrantel pamoate. In terms of actual reductions in fecal egg counts (FEC), the mean percent reductions for all farms were 24.8% for fenbendazole, 99.9% for ivermectin, 73.8% for oxibendazole and 78.6% for pyrantel pamoate. With the exception of ivermectin, these values are far below the levels needed for effective worm control.”

Ok, so I have known this info in general for at least two years and I have just followed the standard worming protocol: worm every two months and rotate  products.

Wormer is cheap.  Collecting poop is…time consuming.

I could have sent the samples off to Horseman’s Laboratory in Illinois.  But here are their prices–I could not tell if that included shipping or not.

1 Sample
2-5 Samples
6+ Samples

The expensive wormer costs 11.20/ tube and you can get Ivermetic for $2.50.

I could have hired a vet to do the fecals. 27.50.

Seriously?  I know how to do this. For the cost of two cups of sugar.

(But I did not do it.)

Until last week.

The Method:

I labelled my ziplocks: Lacey, Toots, LT, Cometa.  I watched for falling turds, and I bagged ’em.

I made my “Sheather’s” Solution.  One cup water, hot + 2 cups sugar.

I got a funnel and made a sieve (from window screen) to fit in the funnel.

Then I took all that to work and gave my microbiology students a fun project! (Optional, of course!)

Here is what we did in the lab.

  • Thoroughly mixed 10ml sugar solution +  3g poo.
  • Filtered it through the screen in the funnel into a 15ml test tube.  (To remove the big chunks.)
  • Centrifuged for four minutes (we have a centrifuge at work and our Lab Tech, who is the best ever, found it, and the 15ml test tubes we needed). Centrifuging drives more of the chunks to the bottom.

  • Removed tubes from centrifuge, filled to the very top with more sugar solution, and put a cover slip on top.

Goat fecal exam from: http://edenhills.wordpress.com/2011/09/02/doing-your-own-goat-fecal-exam/


  • Let sit for five minutes.
  • Placed coverslip on microscope slide and examined!

The Results: According to Eggzamin (a company that will help you analzye your samples), Strongyles and Parascaris are the two egg types we need to care about when looking at a fecal float for horses.

Toots: No eggs.

Cometa:  No eggs.

Lacey: 70 Strongyle eggs per gram.

Picture from the Eggzamin site

LT: About 70 Strongyle eggs and 5 Parascaris eggs (which are rare in horses over  age one, but we saw what we thought we saw) per gram.

From the Eggzamin site, also.

Conclusion: My horses are all “Low Contaminators”!

Horses with egg counts less than 200 eggs per gram are Low Contaminators, 200-300 eggs per gram  = Moderate, and > 500 = High Contaminators.

Mangement implications: In our area, according to Dr. Bobbitt, at East Mountain Equine, Low Contaminators should be dewormed with Moxidectin + Praziquantal in November.

Well, that was lucky timing! It is November!

The Moxidectin + Praziquantal will eliminate all worms (see chart below) including encysted (thus not shedding eggs) small strongyles (cyathostomes) and tapeworms whose eggs sink (thus not detected via this method).  The horses  should be rewormed in May with Ivermectin.   And that is all!

“Moderate contaminators receive one additional treatment of Benzimidazoles or Pyrantel to reduce cyathostome egg excretion during the main season of local transmission [May-November].

High contaminators would receive two additional treatments during this time frame.” (From handout provided by Dr. Bobbitt.)

I have wormer on order from Valley Vet (Horse.com didn’t have cheap Ivermectin)

After treatment, maybe I will search for dead Strongyles in the poop!

Oh and just maybe I will recheck the horses in three months or so. (Or get my micro students to do it!)

About BlogPatty

Here's the skinny: I have a thing for horses. They make sense to me. I have a small horse training business (it's a "boutique" training business, not because it's super fancy, but because the horses get a lot of personal attention). I also go by Dr. Wilber, and teach biology full-time at a Central New Mexico Community college.
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1 Response to Poop! So Eggciting!

  1. Lisa Westfall says:

    Excellent post…very informative for our area, too. Thanks! I had to giggle when I said the word “Parascaris”…sounds like Pair a Scaries! Pretty much describes parasites. lol!

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