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Horse Deworming Schedule & Medicines

Parasites can affect horses just like any other animal, so it's important to prioritize deworming to ensure their well-being. Our Ocala vets provide these valuable insights on horse deworming, including the ideal timing for treatment and strategies to reduce the risk of worm infections.

What Types of Worms Are There and What Problems Do They Cause?

In this article, we will discuss four types of worms that can cause problems in horses. The list is not complete, we are just a selection of some of the most common worms that affect horses.

Small Redworms (Cyathostomes)

This particular worm species thrives within the horse's stomach, making horse parasites a prevalent issue. The eggs of these parasites reside in the intestines, often remaining dormant during the winter months and hatching in spring. T

his can lead to a sudden and substantial increase in parasite population within the horse's body. The influx of parasites can be detrimental as they consume the horse's essential nutrients.

Consequently, it may result in various symptoms such as:

  • Weight loss
  • Diarrhea
  • Colic

Large Redworms (Strongyles)

Large redworms, encompassing various types of strongyles worms, are among the most perilous parasites that can infest horses. Once these worms are ingested, their eggs make their way into the horse's bloodstream. While in the blood vessels, they have a tendency to obstruct the flow of blood, resulting in tissue damage in the areas supplied by these vessels.

Symptoms of these worms include:

  • Colic
  • Rapid weight loss
  • Diarrhea.

Bots (Gastrophilus)

Bots are the worm form of the bot fly. When the bot flies lay their eggs on the coats of the horse, the horse tends to ingest them when they lick themselves to groom. Once in the horse, they hatch and migrate to the stomach.

Symptoms include:

  • Inflammation in the mouth
  • Inflammation in the throat
  • Ulceration in the stomach

Roundworms (Ascarids)

Roundworm is especially dangerous for horses with a weak immune system, like foals and older horses. The parasite is consumed through contaminated food (grass that has come in contact with the fecal matter of an infected horse) or through contaminated food. It migrates from the intestine to either the lungs or the liver. Before returning to the intestines to lay their eggs and start the cycle again, these worms can cause severe damage to the organs.

How Often Should I Deworm My Horse?

How often you need to deworm your horse will depend on a lot of different things. The amount of eggs your horse is excreting in its manure is a key factor.

For most horses, twice yearly, often done in the spring and fall, is recommended. If your horse is highly infected, you should increase the frequency of doses. We recommend consulting with your veterinarian to determine how often your horse needs to be dewormed, based on a fecal examination.

Deworming for foals is often done every 2 months for the first year, with regular fecal exams.

Methods to Avoid Parasites

Besides deworming and regular vet visits with fecal exams, some methods to help control parasites in horses include:

  • If you are getting a new horse, they should be quarantined while they undergo a precautionary deworming and subsequent fecal exam.
  • Remove fecal matter from pasture regularly to reduce reinfection.
  • Rotate pastures to avoid contamination.
  • Do not overcrowd the pasture.

How Can I Tell if My Parasite Control Program is Working?

The best way to tell if you're controlling the parasite is to have your vet do tests, such as fecal exams, to gauge the health of your horses.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Do you need help with your horse's deworming? Contact Florida Equine Veterinary Associates today to request an appointment with our veterinarians!

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