Parasite control - equine

Parasite Control in Horses: Keep Your Equine Partners Healthy

Parasite control is an essential part of every horse owner’s routine care plan. Internal parasites like worms and bots can affect your horse’s health, condition, and performance. Left untreated, they can cause weight loss, a dull coat, poor growth, and even serious digestive issues such as colic. At CVS Online, we’re here to help you understand how to manage parasites effectively and choose the right products to keep your horses healthy year-round.

Understanding Seasonal Worming in Horses

Parasite risks change with the seasons, so adjusting your worming program throughout the year is essential.

  • Spring: As temperatures rise, parasite eggs begin to hatch. This is an ideal time to perform a faecal egg count and treat horses that need it. Tapeworms can also be targeted during spring worming.
  • Summer: Bots and other external parasites become more active. Using a wormer that includes ivermectin or moxidectin helps control both internal worms and bots.
  • Autumn: Another faecal egg count is recommended to assess parasite levels before the cooler months.
  • Winter: Parasite activity slows, but maintaining paddock hygiene and monitoring your horses’ condition helps reduce reinfestation for the next season.

Most common Internal & External Parasites found in Australian horses.

Small Strongyles (Cyathostomes)

Affects the large intestine. Symptoms include weight loss, poor coat, diarrhea and colic. Transmitted via eggs in manure developing into larvae in pasture and ingested by grazing horse.

Large Strongyles (Bloodworms)

Affects blood vessels, especially mesenteric arteries. Symptoms include colic, poor condition & anemia. Least common worm due to modern dewormers.

Roundworms (Ascarids)

Affects mainly young horses below 2 years. Symptoms include coughing, poor growth, pot belly and colic. Transmitted by ingestion of eggs.

Tapeworms (Anoplocephala spp.)

Affects the small intestine and ileocecal junction. Symptoms include colic & poor condition. Transmission from contaminated pasture.

Bots (Gasterophilus spp.)

Larval stage affects stomach lining. Symptoms include mouth irritation, gastric ulcers and poor performance. Transmission from adult bot flies laying eggs on horse's coat and eggs being ingested by horse.

Pinworms (Oxyuris equi)

Affects large intestine and rectum. Symptoms include tail rubbing, irritation around anus. Transmission from ingestion of eggs on pasture.

Lice (Bovicola equi & Haematopinus asini)

Symptoms include itching, hair loss, poor coat and restlessness. Transmission can occur through direct contact with affected horse or through shared contaminated gear.

Smart Parasite Control

Gone are the days of worming every horse every few weeks. Overuse of wormers can lead to resistance, making products less effective over time. Instead, vets now recommend a targeted parasite control program. This can include the following:

  • Faecal Egg Counts (FECs): Testing manure samples to check parasite levels and identify which horses actually need treatment. FEC's identify the amount and type of parasite eggs that are present in horses digestive tract. It is recommended to do FEC testing 3-4 times a year.
  • Selective Worming: Treat horses only when needed, and rotate wormers carefully to avoid resistance.
  • Pasture Management: Regularly remove manure, avoid overgrazing, and rotate paddocks to reduce contamination.
  • Tailored Plans: Foals, adult horses, and older horses all require slightly different approaches. The vets at Cameron Veterinary Clinic can help to ensure your horse is on a program specifically tailored to them.

Working with your vet and maintaining good paddock hygiene are just as important as choosing the right dewormer.

Worming made Easy!

You’ll find a wide range of trusted equine wormers to suit every horse and situation. Whether you’re after a broad-spectrum paste, a bot-targeting treatment, or a rotation option. Explore our range of Equine Parasite products.

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