Effective worm control relies on the correct and responsible use of horse wormers combined with good pasture management.
Follow these tips to ensure responsible wormer use:
- Use faecal worm egg counts (FWEC) during the spring, summer and autumn to assess which horses need worming. Generally horses with a worm egg count of greater than 200 eggs/g should be treated but individual advice should be sought from your vet.
- Target the following worms at the correct time of year with an effective wormer: Encysted Redworm Larvae - late autumn and late winter; Bots - winter; Tapeworm - spring and autumn.
- Worm all horses and ponies at the same time with the same product.
- Use the correct dose: the recommended dosage will vary according to the horse’s weight. Estimate weight as accurately as possible using scales or a weigh tape.
- Don’t rely on the blanket use of the same wormer: this may encourage the development of drug resistance in the parasite population.
- Rotate the active ingredient for each grazing season: select one product type and use for the entire grazing season, then switch to another active ingredient for the next year.
Manage your pasture
A well-managed pasture will help to reduce the worm burden. The following points should be followed where possible:
- Remove droppings on a regular basis (preferably daily, but at least twice a week) and don’t use horse manure as fertiliser.
- Don’t overstock pastures: a maximum of two horses per hectare or 1-1.5 acres per horse is recommended.
- Graze horses of a similar age together – young horses are more susceptible to a higher worm burden.
- Sub-divide grazing areas into smaller paddocks and graze on a rotational basis.
- Harrow pasture during dry conditions to expose soil-borne larvae so that they dry out and die.
- Graze paddocks with other livestock too. This will dilute the horse worm burden on your pasture.