Horse Parasites

Parasites are the single most common cause of illness in horses. Parasites can cause colic, respiratory problems, gastro-intestinal problems, and disease. If a horse has a particularly bad parasite infestation, it can even die. Controlling parasites is a very important part of keeping your horse healthy. Horses need to be dewormed on a regular basis to get rid of as many parasites as possible.

There are four main types of parasites that cause problems for horses. Here is a brief look at the most common parasites that are found in horses:

BOTS

Bots are the larvae of the botfly. Flies lay eggs all over the horse’s body when they land. When the horse licks itself the eggs get transferred into the horse’s mouth where the eggs attach to the lining of the nose, the soft tissues in the mouth and gums, and other places in the mouth and throat of the horse.

Then the eggs work down to the horse’s stomach and attach to the stomach lining. When they mature they are passed out of the horse’s body in manure and then hatch. Then the adult flies land on the horse to lay eggs and start the process again.

Bots are one of the reasons that using pest control products for horses like fly sprays and sheets are so important. Bot infestations are nasty and can cause a lot of illness and distress for horses. Bot eggs can be seen on the horse’s skin, especially on dark colored horses.

The Bot eggs are very small and yellow. They look like yellow grains of sand on the horse’s coat. You can use a Bot knife to scrape them off the horse’s coat. Bots are killed by cold temperatures so after the first hard frost you won’t have to worry about Bots until spring.

There are several different types of over the counter treatments that claim to get rid of Bots but some of them can be poisonous to you and to your horse so you should talk to your vet about a treatment for Bots before you buy any over the counter product. Often, Bots can be taken care of with regular deworming but you should probably buy a Bot knife and have one on hand. If you can see the Bot eggs and scrape them off the horse before the eggs mature you can save your horse a little distress and discomfort.

Since flies are always buzzing around stables you can count on your horse having Bots. You can’t prevent your horse from getting Bots but you can control the Bot population with routine deworming and by checking your horse’s coat during the spring and summer for Bot eggs.

STRONGLYES

Stronglyes are also called Blood Worms. Stronglyes can be extremely dangerous for horses because they are a major cause of severe colic. Immature blood worms travel through the horse’s body using the blood vessels in the intestines and this can cause very severe colic for the horse. Blood worms can also cause severe respiratory and intestinal problems aside from colic and inflammation of the liver and intestines.

The female Stronglye lays eggs in the intestines that get passed out with manure. The eggs hatch, and the larvae settle on blades of grass. The horse then eats the grass and passes the newly mature Stronglyes into the intestines where the process starts all over again. Stronglyes can exist in cold and dry environments by going dormant until the conditions are right again. Sometimes Stronglyes can live for up to 300 days in the horse’s intestine. Female Stronglyes can lay up to 5,000 eggs per day.

Besides causing colic and other problems, Stronglyes can also cause aneurisms in horses. If your horse has Stronglyes then your horse will probably seem weaker than normal and may shake or be anemic from all the Stronglyes sucking the horse’s blood. Your vet can diagnose Stronglyes by looking at the horse’s manure in a microscope to see if there are any eggs or young Stronglyes present in the manure.

ASCARIDS

Ascarids are large Roundworms. Roundworms are a much bigger problem for young horses than they are for older horses. Younger horses need to be dewormed regularly to get rid of Roundworms. Sometimes, young horses can have thousands of Roundworms in their intestines, which interferes with their growth because they can’t get the nutrition they need from the food they’re eating. Symptoms of a Roundworm infection include persistent coughing because the Roundworms travel to the horse’s lungs and are then swallowed when they are coughed up, diarrhea, and sometimes, colic.

TAPEWORMS

Tapeworms are very common in horses and can be very difficult to diagnose. Horses can get tapeworms by eating mites that carry tapeworm eggs during grazing. The eggs mature inside the horse and grow into tapeworms that attach to the horse’s intestine. Regular deworming should help protect horses against Tapeworm infestations.

PINWORMS

Pinworms aren’t technically dangerous for a horse but can cause a lot of discomfort. A sure sign of pinworm infestation is when the horse starts rubbing its tail on the stall door, the wall, or anything that is at tail height. Pinworms live in the anus and crawl halfway out to lay eggs, which causes severe itching and distress to the horse. Pinworms can be treated by a vet and regular deworming can help prevent further Pinworm infestation.