Forgot your password?

Understanding External Parasites that Affect Your Horse

By Edited Aug 22, 2016 0 0

How aggravating is it to be "bugged" with flies, mosquitoes, ticks or other insects?

Horses experience the same discomforts with parasites that humans do!

A parasite is a plant or animal that lives on, in, or with another living organism.  This is called a host.  The parasite will derive food and shelter at the expense of the host.  External parasites of horses usually bite (with the exception of certain flies) and will suck blood for food, and use the body temperature and the hair of the host for comfort and shelter.

Younger horses and foals are more susceptible to all types of parasites.  When they are attacked by external parasites it can result in problems with temporary development and in some cases even permanent growth.

Most horses encounter problems with external parasites.  With constant exposure the animal will suffer other side-effects such as poor nutrition, stress, mild forms of disease, and sometimes conditions of general neglect.  External parasites are easier to control and eliminate than internal parasites but must be accompanied with a total health program or the treatment may be disappointing.

There are five common external parasites that usually affect horses.  Two of these can be communicated to humans; ringworm and mange mites.


Horse Fly

 There are many different flies that will attack horses and all types vary in the way they affect the animal.  As a constant source of annoyance, flies make animals, especially horses, restless and appear  ill-at-ease.  The house fly and the face fly will feed on the skin, nasal and eye secretions but they do not bite.   Horn, stable, deer and horse flies all will bite and suck blood.  They can be very persistant and carry serious equine diseases.  Blow flies come in two different types, are very common in most areas, and lay eggs in wounds a horse might have.  One type will hatch maggots and the other will hatch screwworms, both of which can cause severe damage and sometimes death of the animal.  They both can be eradicated by cleaning, dressing, and caring for wounds immediately.

Fly control is typically done by making sure the habitat of the animals are clean and free from waste, decaying vegetable materials, and rotting feed sources.  Use of screening can help if it is practical.  Pesticides can be used as a control and treatment. 



Both the biting and sucking kind of lice will affect horses.  They thrive in long hair and poor groomed or uncared for horses are good breeding grounds for lice.  Horses with lice will be seen rubbing, biting, and have patches of skin without hair.  They will look to be in poor condition after a time.

Proper nutrition, good and regular grooming, and clean housing conditions will help prevent louse infestations.  Lice can be carried from animal to animal on saddles, blankets, brushes and in dirty stables and pens.  Horses can be dipped, sprayed, sponged, or dusted with a lice control treatment.  Treatment should be repeated two to three weeks to insure that the infestation is controlled by destroying eggs before they hatch.



These microscopic egg-laying creatures cause a disease known as mange in horses.  Symptoms of mite infestation includes itching, irritation, inflammation, loss of hair, crusty scabs on the hide, and the folding of the skin.

Mange is difficult to stamp out in all animals.  Dusts are not effective.  Spraying and thoroughly wetting down the horse with the proper insecticide every week is required until you have the condition under control.



These biting insects can be carriers of serious equine diseases as they attach to the host and feed on the blood. 

In some cases, dipping the entire animal is the only way to eradicate ticks.   If the horse only has a few ticks they can be swabbed with alcohol or chloroform or use of an insecticide will work.



Ringworm is caused by various species of fungi and will form a circle on the skin.  It is generally not a serious problem unless the ringworm penetrates the skin deeply, which will cause the animal discomfort and severe itching will result.  There could be a secondary infection which may lead to abscesses. 

If there are only a few ringworm lesions, they can be soaked with warm soapy water and then after scraping off the crusty patches, paint with tincture of iodine every day for a week or two.  If the ringworm is very severe consult your veterinarian.  Make sure you wear gloves and wash thoroughly after treating as ringworm can be transmitted to humans very easily.

Most insecticides are poisonous and must be handled correctly.  All label instructions should be followed for use and storage.  Avoid contaminating feed and water and keep from other animals and children.

It is advisable to always consult your veterinarian before diagnosing and treating your horse.




Add a new comment - No HTML
You must be logged in and verified to post a comment. Please log in or sign up to comment.

Explore InfoBarrel

Auto Business & Money Entertainment Environment Health History Home & Garden InfoBarrel University Lifestyle Sports Technology Travel & Places
© Copyright 2008 - 2016 by Hinzie Media Inc. Terms of Service Privacy Policy XML Sitemap

Follow IB Home & Garden