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How do Fecal Egg Counts save $$ on worming??

How do Fecal Egg Counts save $$ on worming??

How do Fecal Egg Counts save $$ on worming??


  • Fecal Egg Count (FEC) measures the number (Low/Med/High) of worm eggs a horse sheds. This is used as an indicator of level of worm burden and also the horse's natural immunity to worm infestations. A high egg shedder can indicate a high worm infestation and low natural immunity.
  • To save $$ on wormers you need to commit to a 12 month program of Fecal Egg Counts.
  • Year 1: Implement a combined Fecal Egg Count & Worming Program or a Fecal Egg Count Program These programs will help determine if your horse is a low, medium or high shedder of worm eggs.
  • Year 2 onwards: Chooses a Low, Medium or High FEC worming program based on your horse's natural worm shedding level + an Annual Fecal Egg Count.  
  • As 20% of the horses shed 80% of worm eggs - only 1 in 5 horses will have a ongoing high FEC. The other 4 only need two wormers and a fecal egg count each year.  If you know what is really going on in your horse, rather than guessing, you will very likely find your horse is a low shedder and save $$$ by using less wormers.

On a property with a low to moderate level of worm egg pasture contamination, a minority of horses are likely to have persistently high FEC’s. The 80:20 rule applies: 80% of worm eggs are excreted by 20% of the horses (Lester et al, 2013a, b;  Kaplan and Nielsen, 2010). By targeting wormers to treat the high FEC horses, the level of contamination on the pasture can be lowered (assuming good paddock management practices) reducing frequency of wormers required on the property. (Van Wyk, 2001)

If you can only afford one fecal egg count per year, run it right before worming your horse in the spring.  Note: a one-off FEC cannot be used reliably to indicate if an individual horse is an ongoing high or low FEC horse, this requires a 12 month commitment to fecal egg testing.  

Three FECs over 12 months (NSW DPI suggests August, January & May) will give a pattern of each horse's natural resistance to worms. (Equine de-worming: a consensus on current best practice UK-Vet Equine | Volume 3 No 1 | Jan/Feb 2019). 

EasyWormer Programs Featuring Fecal Egg Counts

The FEC data collected over this year can show you which horse(s) on your property need to be treated with wormers more regularly.   The egg shedding characteristic of horses is very stable over time, when it is otherwise in good health, pasture management practices are sound, and the horse has not recently moved from one property to another.

So, a healthy paddocked horse with a record of low egg shedding/FEC will tend to always have a low FEC, while a high egg shedder/FEC horse will tend to always have a high FEC (Nielsen et al., 2006; Becher et al., 2010).

After this testing period, low shedders/FEC count horses may require just 1-2 wormers and one FEC each year.  High shedders may require more wormers throughout the year – but remember due to the 80:20 rule this may be just 1 in every 5 horses. 

EasyWormer offers a worm control programs for those that know their horses level of egg sheding/FEC count here and you just need to add the Annual Fecal Egg Count (FEC) here.  If you're horse's FEC continues to be low we will cancel the spring wormer - saving you even more!

Crunching the numbers

Here’s the maths for a single property with 5 horses using EasyWormer 5 horse order pricing:

Original worming program: $107.70 per horse per year

  • Worming every 8 weeks for 5 horses: 6 wormers x 5 horses x $17.45 a wormer = $538.50 or $107.70 per horse per year

FEC Testing Period (suggested 12 months to get a good reading of egg shedding average): Cost = $136.35 per horse

  • One year of Fecal Egg Counts x 5 horses: 3 x FECS x 5 horses *$27.50 per test = $412.50  PLUS
  • 3 wormers a year x 5 horses x $17.45 = $261.75 (if all wormers required, could be less)

Total $674.25 per year or $134.85 per horse   Easywormer offers this program here.

    Post FEC Testing period  Cost = $69.38 per horse (average) 

    • FEC testing once per year = 1 x per year x 5 horses *$27.50 per test = $137.50 PLUS
    • Wormers for 1 horse with history of medium/high Fecal Egg Count: 1 horse x 4 wormers per year x $17.45 = $69.80  PLUS
    • Wormers for 4 horses with history of low FEC counts: 4 horses x 2 wormers per year x $17.95 = $139.60  

    Total: $346.90

    • Equals an average cost of $69.38 per horse
    • Saving over $38 per year per horse (35%) on original worming plan
    • Extra costs for FEC testing period are paid back in less than one year with savings made.

      Not only is this cheaper, but is a more effective program, that also helps slow down any worm resistance that may occur on your property.

      What do you think? Do you think its worth giving fecal egg counts a go?



      This information is not a recommendation or advice. EasyWormer strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.

      Veterinary advice should be sought both in relation to parasite control programs and prior to undertaking any parasite treatment program.



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