When Should You Worm a Horse in Australia?

When Should You Worm a Horse in Australia? main image When Should You Worm a Horse in Australia? image
Not sure when to worm your horse in Australia? This seasonal guide explains the best times to worm in spring, summer, autumn, and winter, with clear advice for foals, young horses, and adults. Keep your horse protected year-round.

When Should You Worm Your Horse in Australia? Seasonal Guide

Knowing when to worm your horse is just as important as knowing which wormer to use. Many horse owners grew up with the idea of worming every 6–8 weeks year-round, but modern best practice shows that this approach is outdated and can actually increase worm resistance. Instead, worming should be based on the seasons, your horse’s age, and faecal egg count (FEC) results.

Why Timing Matters in Worming Programs

Worms thrive in mild, moist conditions and decline in extremes of heat or cold. That means Australia’s seasonal changes have a big impact on parasite risk. By targeting worming treatments at peak activity times, you protect your horse’s health while avoiding unnecessary dosing.

Seasonal Worming Guide for Australian Horses

Spring (September–November)

As the weather warms and pasture grows, strongyle activity rises. Tapeworms are also more common in spring because their intermediate hosts, pasture mites, thrive in mild conditions.

  • Target: Strongyles and tapeworm.
  • Recommended: Equimax Plus Tape for broad protection, including tapeworms.

Summer (December–January)

Parasite activity varies depending on region. In hot, dry inland areas, worms are less active. In coastal or tropical regions, warm and humid conditions keep strongyles active.

  • Target: Treat only if FEC results are high. A broad-spectrum wormer like Virbac Equimax is a reliable choice if needed.

Late Summer to Early Autumn (February–March)

This is the time to address bot larvae that develop in the stomach after bot flies lay their eggs in summer. Strongyles are still a concern in wetter regions.

  • Target: Bots and strongyles.
  • Recommended: Virbac Ultimum for strong, broad coverage.

Late Autumn to Early Winter (May–June)

Another strategic worming time to reduce parasite levels before the colder months. Tapeworm treatments are often included here as part of a “foundation” dose for adults.

  • Target: Strongyles and tapeworm.
  • Recommended: Virbac Strategy-T as a trusted rotation option.

Winter (July–August)

In cooler inland areas, worm activity is low, and treatment may not be necessary. In warmer coastal zones, parasites may still circulate.

  • Target: Only treat if FEC indicates a problem.

Foals, Young Horses and Adults: Different Needs

  • Foals and yearlings: Require 3–4 worming treatments per year, focusing on roundworms (Parascaris) and strongyles.
  • Horses 1–3 years: Still need regular treatments, usually 3 per year.
  • Adult horses over 3 years: Most only need 1–2 treatments per year (spring and late autumn), with extra doses for horses that are consistent high shedders.

Smarter Worming for Long-Term Health

The best approach to worming is strategic: use FEC testing to monitor egg counts, treat only when necessary, and always choose the right wormer for the season. This reduces resistance, saves money, and keeps your horse healthier.

Browse our full range of horse wormers, including Equimax Plus Tape, Virbac Ultimum, and Virbac Equimax, to keep your horses protected all year round.