Worm management
Ask us about managing your horse’s worm burden
We recommend carrying out a risk assessment of your horse/yard annually and adapting your worm testing program accordingly.
Recommended tapeworm test timings are indicated below, but you can test at any point if no testing or treatment has been conducted within the previous six months.
November to January: Assess your horses' parasite risk. For low risk horses, no treatment is appropriate. For medium risk horses, treat with ivermectin or carry out a redworm blood test. For high risk horses, deworm with Equest.
March: Test for tapeworm and worm egg count.
March to October: For high risk groups, we recommend worm egg counts every eight weeks. For low risk groups, worm eggs can be performed every 12 weeks.
May: Worm egg count.
July: Worm egg count.
September to October: Test for tapeworm and worm egg count.
For further support, please contact the practice.
Worm management program
What’s the worry with worming?
Many horses do not need routine wormer treatments. The unnecessary use of wormers contributes to increasing anthelmintic (wormer) resistance in equine parasite populations and environmental contamination with anthelmintic drugs which are harmful to many wild invertebrates (eg. dung beetles).
Individual horses differ in their own response to worm infections, and identifying those that are high egg shedders to target for worming treatments when needed, along with good pasture management, helps to keep our horses' worm burdens at a healthy level.
This can also help to reduce pasture contamination and re-infection rates and protect our wormers against the development of resistance, so that we can continue to use them when needed to prevent worm-associated disease.
While many horses do not need routine wormer treatments, the risks of ignoring a horse’s worm burdens are significant.
Gastrointestinal parasite infections can cause serious disease if left unmonitored, with symptoms including:
Colic (medical and surgical).
Weight loss.
Diarrhoea.
Restricted growth (youngstock).
Blood vessel blockages.
Intestinal damage, causing life-long nutrient absorption problems.
Itching and discomfort around the anus and tail-head (pinworms).
Advantages of using our targeted worming program:
Individual assessment of a horse’s worm ‘risk’ and egg shedding level.
Focus on management to reduce egg shedding and the need for wormer treatments.
Inclusive post-treatment* testing ensures any wormer treatments given are effective (and if not, swift interventions and tailored plans can be made if resistant worm populations are identified).
Expert advice given on when to test, when to worm.
All gastrointestinal worms considered, including those not detectable in routine faecal egg counts (encysted small redworm, tapeworm and pinworm if applicable).
* Where we supply the worming treatment.
Program outline
You can download our risk assessment form here. Alternatively, you can use this online resource: https://www.whatsyourwormrisk.com/.
Faecal egg counts (FEC) every 12 weeks (low/medium risk horses) or eight weeks (high risk), February to November inclusive. Click here for faecal sample collection instructions.
Supply of two EquiSal tapeworm tests per year in spring and autumn (or, every six months). Please see the EquiSal site for more information: https://www.equisal.co/the-equisal-test.
Any FEC indicating a wormer treatment is needed includes a free 14-day post treatment* test to check for treatment efficiency.
This program is suitable for adult horses over four years old.
Current prices for 2025 are: £13.50 for FEC samples and £23.50 for EquiSal tapeworm test kits. Young animals and pregnant mares need special consideration – please contact us for advice and a suitable plan.
We also offer bespoke yard worming programs, inclusive of an on-yard risk assessment for parasite management – please get in touch for a tailored package.
Management tips to reduce the need for worming treatments
Poo-pick pasture once weekly (twice weekly in summer). This is the most eƯective management tool we have to reduce worm burdens on grazing pastures!
Test before (and after) giving wormer treatments.
Avoid spreading horse manure on pasture grazed by horses, e.g. harrowing.
Avoid overstocking and overgrazing.
Rotate grazing with sheep or cattle or rest pastures regularly (this is best done in hot weather).
Avoid moving horses to clean pasture within two weeks of worming. Although once recommended, we now know this practice is high-risk for increasing wormer resistance as only resistant parasites would move with the horses to contaminate the new pasture.
Muck out stables regularly, especially when they contain foals and weanlings.
Muck heaps should be separated from grazing areas – worms can migrate many metres across pasture.
Discuss appropriate quarantine management for new horses arriving on the premises with your vet or RAMA (formerly SQP) to avoid introducing resistant parasite populations.
Common worming pit-falls to avoid
Routine worming without testing – did your horse need it, did it definitely work?
Using the wrong wormer, or at the wrong time – not all wormers/parasites are the same! Rotating wormers – whilst once recommended, this does not protect against the development of resistance. Confusingly, many wormers with diƯerent names contain the same active drug too.
Poor sampling technique for faecal egg counts.
Incorrect wormer dosage, especially under-dosing (if using a weigh tape to estimate your horse’s weight, add 10% for the wormer dose).
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