General Worming Advice

To worm or not to worm?

That really is the issue.  Whether you have a single horse in an isolated paddock or are sharing a field with several other owners, what is the best policy?

Simply there is no PERFECT policy but what BEST in reality fits your particular situation. 

Where do you start?

  1. Are you going periodically take Dung samples and treat ONLY if necessary?

Dung samples give an indication of the Adult round worm population living in your horses intestines.  Levels are generally classified as so many eggs per gram.  You may decide to accept a low level of infestation, such as below 200 epg and only treat when above this level.  Dung samples should be repeated every 8-14 weeks according to your confidence in the system.


  • Tapeworm eggs are not reliably found in feaces.  Horses should be treated once yearly (or twice in certain cases) using either a ‘Combined’ wormer, Double dose Pyrantel or Equitape.

  • Encysted Redworm are an increasing problem.  Small redworm larvae migrate through the large bowel gut wall and then hibernate there for a period of time before exiting and maturing into adults.  Whilst burrowing into and then out of the gut wall, damage is done that can lead to weight loss and diarroea. Larvae are causing the damage and not egg produding adults so there may be no rise in the feacal egg count.

  • Bots over winter attached to the stomach lining and do not produce eggs.

  • Pinworm lay their eggs around the anus so will not be in the feaces.

2. Or are you going to reguarly Worm your horse throughout the year?

Regular worming requires a little thought into when to worm, against what and how often you should be dosing.

  • Ensure an accurate estimation of Body weight is done using a Bodyweight Tape measure.  Add about 10% to allow for any underestimation of Bodyweight.
  • Each wormer type has a different interval between repeated treatments, Ivermectins about 10-12 wks, Pyrantel about 6-8 wks and Moxidectin 14 wks.
  • Treat appropriately means Tapeworm, once/ twice yearly, Encysted redworm in Late Winter, Bots in Late Winter and Roundworms thoroughout the summer months.

BEWARE:  resistance to wormers will occur if YOU worm TOO frequently, with TOO little wormer and use the WRONG product and the WRONG time of year!

We are told there will be no more new wormers so we need to protect what we have now for the future!