Photo Of The Day

By guest author Thomas Brown,

What Is Deworming Your Horse: Things To Consider

Worms are a common problem among many species, and horses are not an exception.

These parasites can live in the intestines for a long period of time and you can not even know about it. A low number of worms make no harm to a horse, however, excessive parasites may cause severe health issues. Thus, it’s vital to discover the problem before at an early stage.

Two horses grazing

You should constantly keep your horse’s well-being under the radar to control the population. Therefore, we decided to outline some crucial aspects that have to be considered about horse deworming.

A horse in a pasture scratching its leg

Image by rihaij on Pixabay

Disclaimer does not warrant the accuracy or timeliness of any of the information found on the website, and does not accept liability for errors or omissions.

In addition, anything found on is not intended to replace veterinary care for your horse or other animals. Always consult a veterinarian or other trained animal health care professional regarding any information that may be found here, and/or regarding the health or health care of your animals.

The Most Common Types of Worms

There are several species of parasites that could be found in horses. These worms can get into an animal in different ways and cause a range of symptoms.

Strongyloides Westeri

Strongyloides Westeri is a threadworm that infects young foals. The parasites are transmitted from mares with milk. Thus, it’s crucial to check a gestated mare for worms on an ongoing basis. If the helminths (worms) are under control, the foal will develop a strong immune system to handle the worms. In case of severe infection, diarrhea and dermatitis may occur.

Larval Cyathostomes

These are small red worms that can be eaten by a horse with grass on pasture. The larvae reproduce in the large intestine, then they grow up and lay eggs. The eggs come out with horse’s feces and they become larvae over time. That’s the lifecycle of Larval Cyathostomes.

This species needs specific conditions to start growing. Usually, they start developing in spring when it’s getting warmer. Until that time, they may survive in the intestine. The common symptoms of the redworms are diarrhea, weight loss, gas, colic, and lethargy.


Strongylus Equinus is a species of large red worms that have a similar lifecycle to Larval Cyathostomes. They could be swallowed with grass when a horse is grazing around. When the larvae hit the recipient, they go through the blood vessels of the liver and intestine. This may lead to inflammation and vessel obstruction. The mains symptoms include diarrhea, gas, and colic.


As its name implies, the lungworms (Dictyocaulus Arnfieldi) is a parasite that may be found in the lungs. Usually, donkeys can transmit the larvae to horses, however, the horse-to-horse transmission also takes place. When the donkey’s infected feces gets onto the pasture, the horse may pick up the larvae by eating the grass nearby.

The signals you should be aware of include lung sounds in horses. The prolonged worm living may lead to bronchitis and pneumonia. Additionally, the symptoms are diarrhea, weight loss, and colic.


Tapeworms (Anoplocephala Perfoliata) are the parasites migrating through the intestine. The mite serves as a host that typically live on pasture and hay. Mites eat the larvae eggs, horses eat mites, and get infected. The common symptoms of tapeworms are diarrhea, and weight loss. As well as severe colic that may need emergency surgery.

Bot Fly Larvae

Gasterophilus Intestinalis occur from botflies. The adult flies lay eggs on horse’s legs and when horses lick their limbs, the eggs get into an animal. Gasterophilus Intestinalis develop in the stomach, which may lead to ulceration and ruptures. The Botfly Larvae signs are the inflamed mouth and colic.

A woman petting ponies

Image by Tatiana on Pexels

Horse Deworming Guidelines

In order to keep the helminths under control, regular deworming is needed. Here’s a list of useful tips that you should keep in mind.

Provide Worm-Free Surroundings

A few actions should be taken in order to control the helminths’ intrusion. They may reduce the chance of getting complications and repeated infection.

The Bottom Line

Look after your horses carefully and in case of health worsening, contact your vet with no hesitation. Immediate actions may prevent severe health issues, so your companion will live more comfortably. Discuss a deworming schedule with your veterinarian to control the infection. Stay healthy!

This article was contributed by guest author Thomas Brown for

About The Author

The team at is focused on helping you find horse-related facilities and services near you. Their directory of boarding facilities, veterinarians, riding instructors, fence builders, and more is designed to help you find what you and your horse need in your own area.


What Is / Are...

What Are 5 Of The Biggest Wild West Robberies?

What Are 5 Reasons Horse Trailer Lighting Matters?

What Are 8 Dumb Things To Say To A Horse Lover?

What Are 9 Proven Ways To Keep Flies Off Horses?

What Are Chestnuts and Ergots?

What Are Cowboy Chinks?

What Are Ermine Spots?

What Are Horns?

What Are Horse Blood Marks?

What Are Horse Vaccines and How Do They Work?

What Are Horse Whiskers?

What Are Leads?

What Are The Parts Of A Western Saddle?

What Are Saddle Rigging Positions?

What Are Some Fencing Options?

What Are Some Foods Both Horses And Dogs Can Eat?

What Are Some Horse Fencing Basics?

What Are Some Interesting Horse Facts?

What Are Some Interesting Charts and Graphs With Horse Information?

What Are Some Options For Temporary Horse Fencing?

What Are Slobber Straps?

What Are Synthetic Saddles Made Of?

What Are The Rodeo Catch Pens?

What Are The 10 Best 3-Horse Trailers With Living Quarters In The USA And Canada?

What Are The X's In A Cowboy Hat?

What Are The Three Legal Head Catches?

What Are Wolf Teeth?

What Is The Angle System For Branding?

What Is The Barrel Racing Pattern?

What Is A Bosal?

What Is A Brand?

What Is A Bull Riding Vest Made Of?

What Is A Crow Hop?

What Is Deworming Your Horse?

What Is A Domain Name?
Why would I need one for my farm or ranch even if I don't have or want a website?

What Is A Fifth Wheel Trailer Hitch?

What Is Flag and National Anthem Etiquette At A Rodeo?

What Is A Slant Load Horse Trailer?

What Is Floating A Horse's Teeth?

What Is Freeze Branding?

What Do Horse Freeze Brands Look Like?

What Is A Galvayne's Groove?

What Is A Gooseneck Trailer Hitch?

What Is A Hack Rein?

What Is A Headstall?

What Is Some History About The First National Finals Rodeo?

What Is The History Of The Modern, Hornless, Bronc Riding Saddle?

What Is The History Of The Modern Rodeo Bucking Chute?

What Is The History Of The One-Hand Bareback Rigging?

What Is The Nasolacrimal Duct In Horses?

What Is A Pony Express Mochila?

What Is Hermann Oak Leather?

What Is Larvicidal De-Worming?

What Is The Flehmen Response?

What Is The Flying Gallop?

What Is The Mark Out Rule?

What Is A Nord Fork?

What Is The Rodeo Return Gate?

What Is Rotational Grazing?

What Is A Safety Tip For Posting The Colors?

What Is A Slick Fork Saddle?

What Is A Spur Ledge?

What Is A Swell Fork Saddle?

You Might Also Like

How To

Horse Tips

Who Was


Molly's Custom Silver uses and recommends Molly's Custom Silver!

FREE Newsletter!
Receive tips, how-to's, and other good stuff. Subscribe now!

Some images and/or other content on this website are copyright © their respective owners.
All other material copyright © 1999 - 2024 by - All Rights Reserved

Menu    About / Contact    Newsletter

Disclosures    Privacy Policy