Worming Horses

A very common question we get here in the clinic is how often do we need to be worming horses?

The frequency of worming is very dependent on the age of the horse and the stocking rate of the property. It is important that you talk with your vet for a customised plan for you but below are a few helpful guidelines on where to start:

  1. Faecal Egg Count (FEC) should be carried out for all horses on your property at least four times a year. It is important that all horses are checked as every horse is different. A FEC can be carried out in clinic and can tell you if there is a need for drenching. FEC can also be carried out 10 to 12 days post worming as well to determine if the drench has worked.
  2. All horses need worming in Autumn. Cyathostomes (small redworms) can be a problem and they are unable to be detected using the current testing methods we have available. It is important that the wormer contains moxidectin and praziquantal. In our clinic, Ultra-Mox is the wormer that would be appropriate for that time of the year.
  3. Pasture management: It is important that we do not solely rely on the wormer to control parasites. Rotational grazing with sheep or cows is a great way to reduce pasture contamination. Removal of faeces from the paddock at least one to two times a week. Faeces should be removed completely and ideally composted so the parasites are killed off (>40°C temperature required for extended periods.) Harrowing is not recommended.

Pinworms (Oxyuris equi) are not life threatening but can cause quite a bit of irritation around the tail and rectal area and cause the horse to become restless and irritated. Hair loss can occur around the back end and the tail due to rubbing. This can be a problem in competing horses. These parasites can’t be picked up in FECs but can be diagnosed by a vet visit. A wormer such as Equimax® LV would be a good option for treating this parasite.

General Foal worming recommendations:

  1. Should have their first wormer around 2-3 months of age. This can be repeated at around 5 months of age. It is important that the wormer used contains Fenbendazole. At our clinic this would be Panacur®.
  2. FEC should be carried out at around 7 months of age to determine if a follow up dose of drench is required.