Winter Worm Control For horses tapeworm testing Spring/Autumn

Winter worm control

For horses tapeworm testing Spring/Autumn

The winter protocol varies slightly compared to the other seasons as we need to consider targeting encysted redworm.

This information is for subscribers that have chosen to test their horses for tapeworm in the Spring and Autumn and need to know what their winter parasite control programme will be.

There are a number of things to take into consideration for each individual horse; we know that it's tempting to want a date in the calendar but in practice parasites don't have diaries and we need to consider factors such as environment, ground temperatures, if your horse may qualify for the small redworm blood test and also your horse's overall parasite control programme.

🚨 Please wait to hear from us first before worming for encysted redworm so we can provide you with the best winter treatment plan for your horse.

The information below outlines the general principles and gives you an idea of what to expect.

🌱🍂 If you test for tapeworm in Spring/Autumn then you will have had a worm egg count and an EquiSal saliva test to complete for your horse(s) in either September, October or November. Going into the winter months encysted redworm and potentially bots are therefore the main parasites to target. 

  1. Between December and February we’ll send a worm egg count. Test your horse and WHATEVER the result, treat for encysted redworm. We can advise which wormer is best for your horse, taking into account test and worming history, age, environment and general health. 
  • Moxidectin (Equest and Equest Pramox) is the preferred treatment for encysted redworm, particularly if targeting bots at the same time.
  • There are circumstances where a 5 day course of fenbendazole (Panacur Equine Guard) is more appropriate to treat encysted redworm  where moxidectin is contra-indicated and for young horses under four who are also susceptible to roundworm infection.
  1. If the winter worm egg count comes back positive, we’ll send you a reduction test to help monitor drug resistance and check that treatment has been effective. Worm and 10-14 days later take another worm egg count.

  2. Horses on the high risk programme will worm count again later in the winter – in exceptional circumstances a second treatment for encysted redworm may be required. 

Small Redworm Blood Test

According to advice, horses with previous faecal egg count results >200epg within the last year are considered high risk and may not be appropriate for this innovative new test, so we will advise that you should give a routine worming treatment.

If your horse is classed as low risk <200epg within the last year, is in a closed herd with good paddock management and there is frequent poo picking, then we will be in touch to suggest that you chat with your vet further about this test.

Every horse that does not require a moxidectin dose is helping preserve to the chemical and delay resistance.

Test Results

If you are not sure what the results mean then we have a handy guide on our website 'What Do My Results Mean?' or if you still aren't certain then please contact us via email or phone.


⚠️ Moxidectin shouldn't be given to underweight horses, foals under 4 months old (6.5 months if also combined with praziquantel) and isn't licenced for donkeys. We also advise caution if using it in miniature Shetlands unless you can calculate dosage accurately. This is because the active ingredient is stored in body fat and these animals don't have sufficient stores to take up the drug.