How do I know if my horse needs to be wormed?

Worried about worming your horse? Here, vet Wendy Talbot explains how to know when your horse needs to be wormed. 

Worming your horse in spring

Between spring turnout time and October, the best method is to use a faecal worm egg count (FWEC) every six to eight weeks.

To do this, you'll need to take a dropping sample using a collection kit provided by the lab that will carry out the count.

This will identify the horses that need doing for redworm and those that don't. 

Using regular FWECs saves the cost of worming horses unnecessarily during the summer, while protecting the health of those that need treating. 

It also helps to preserve the effectiveness of wormers by slowing resistance. 

Worming your horse in winter 

During winter, FWECs are less useful. Many horses spend less time at grass and so won't pick up worms through grazing - worms also don't breed in such great numbers when the temperature drops. 



On this basis, FWECs can be misleading, simply because fewer eggs may be produced. 

Despite this drop in reproduction, encysted small redworm (ESRW), lying dormant in the gut wall, remain a threat to your horse's health over the winter. 

These won't show up in a standard FWEC, so during winter and early spring, it's advisable to worm with a specific wormer to treat for ESRW. 

Tapeworm and bots won't show in a standard FWEC either, so you should also treat for these, on your vet's recommendation. 

Alternatively, for tapeworm, you can ask your vet to conduct a separate tapeworm test using a blood or saliva sample. 


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