Fire Ant Bites in Horses

Fire Ant Bites in Horses - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost

Most common symptoms

Itching / Pain / Redness / Swelling


Rated as moderate conditon

1 Veterinary Answers

Most common symptoms

Itching / Pain / Redness / Swelling

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Fire Ant Bites in Horses - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost

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What is Fire Ant Bites ?

If you live in the southeastern part of the United States as well as parts of Texas, the term “fire ant” is truly well known to you. Most likely, if you live in these areas, you have experienced the vicious burning bite of these imported pests more than once to be sure. While humans are susceptible to these bites, animals also don’t have any real protection or immunity to them. Your horses, regardless of age, and any other animal on your farm is a target for their venom and, they especially like neonatal foals and otherwise weakened equines.

The imported red fire ant, its scientific name Solenopsis invicta Buren, is a vicious insect which was brought into the United States through the port of Mobile, Alabama in the 1930’s and has had huge impacts in the southern U.S. This insect is spreading to the northern sections of the U.S., promising to wreak havoc wherever it lives.

Symptoms of Fire Ant Bites in Horses

The symptoms of fire ant bites on your horse are very similar to those we humans experience in our unfortunate and unintentional contacts with these pests:

  • Intense pain in the bite area
  • Pruritis - itching around the bite area

  • Erythema - redness around the bite area
  • A pustule with a red halo around the bite develops within 24 to 48 hours

These are the general symptoms you would likely notice if your horse it bitten, quite similar to those which you suffer from the bites. The resulting symptoms are irritating to the adult horse to be sure but not usually deadly. For the neonatal foal or otherwise weakened adult horse who spends a great deal of time in the recumbent position, the threat is much higher due to the opportunity for a greater number of bites from the fire ants while laying on the ground, the amount of venom being injected into their systems being greater with the greater number of bites.



There really aren’t any specific types of fire ant bites -- they are just painful, itchy insect bites. That being said, it is important to note that fire ants will bite their victim anywhere where the hair is absent or sparse. This means that your horse can suffer bites on the ears, eyes, muzzle, genital region and underbelly. Some of these areas are particularly tender and will require some specific care after the bite to promote appropriate healing.

Causes of Fire Ant Bites in Horses

The cause of fire ant bites in horses is quite simply just being in the near proximity of the ant hill or mound. Here are some things which will be helpful to know:

They will bite healthy animals on occasion but the real victims of their vicious bites are those who are weakened, for example neonatal foals and sick, weak and aged older horses. These categories of horses are at a greater risk of serious injury and death as they are more likely to be laying on the ground, allowing greater exposure to the fire ants to bite and inject their venom into the already very susceptible animals. 

Lesions or bites around the eyes, lips, nostrils, anus and vulva are particularly painful and can be very serious, with the eyes being the most critical of them all. The fire ants are drawn to these areas as they are moist and warm. With multiple bites to these areas, the skin and tissues can be greatly inflamed, making them very uncomfortable and significantly affected by the necrosis caused by the venom in the bite. 

Some animals can be bitten by literally hundreds of fire ants in a short space of time and, as licking the wound is the normal response to the irritation caused by the bites, some animals have also been found to have fire ant bites in the upper intestinal system and esophagus when examined under necropsy.

Diagnosis of Fire Ant Bites in Horses

The diagnosis of fire ant bites in horses is made primarily upon physical examination and clinical signs. The condition of the horse, whether foal or aged horse, is determined also by physical examination and assessment of signs and symptoms which are being exhibited by the afflicted horse. The extent to which the equine is deteriorating will likely commensurate with the number of fire ant bites sustained by the animal.

This, as well as the overall general health of the equine, will be considered when developing and implementing an appropriate treatment plan. In the development of that treatment plan, attention will be given to the places most affected by the bites and recommendations will be made accordingly. In cases involving multiple bite areas, recommendations may include differing treatments for the different zones of injury to be treated, for example, treatments for the eyes will be different from those recommended for bites on skin surfaces.


Treatment of Fire Ant Bites in Horses

As mentioned above, treatment plans will be reflective of the bite zone to be treated. The eyes are of critical concern when making recommendations for treatment of fire ant bites in horses. Fire ant stings or bites to the ocular adnexa can be quite serious as the tissues of the eyeball are quite sensitive to the necrosis that ensues from the sting. Scarring and corneal ulcers can develop on the cornea, which, if not treated appropriately and timely, can progress to devastating degrees. The tissues of the eyeball and cornea can actually decompose, causing the equine to lose the eyeball. Treatments will likely include but are not limited to:

  • Direct attention from your veterinary professional that addresses both the immediate effects of the venom intoxication and the secondary effects of the sting or bite injury itself (spraying the victim with a low toxicity insecticide or with soapy water to kill the fire ants which may still remain on the horse)
  • Infusion of IV fluids to rehydrate those animals whose hydration is in question
  • Nonsteroidal anti inflammatory medications to neutralize shock, reduce swelling and aid in pain relief
  • For severe shock cases, intravenous fast-acting steroids may be administered - longer lasting ones will inhibit the healing of the corneal epithelium of corneal ulcers

  • Some veterinary professionals may wish to begin systemic antihistamines for the correction of histamine reaction at the wound site - some feel that this may not help much if the stings or bites are more than 30 minutes old
  • For afflicted eyes, treat with antibiotic topical solutions every 4 hours - steroids may be utilized if there is no corneal ulcer present

  • Possible gastric lavage to remove remaining ants from the intestinal system

Recovery of Fire Ant Bites in Horses

There may be continuing care required for some situations involving fire ant bites in horses. Here are a few things that might be required:

  • Bacteremia (bacteria in the blood) can sometimes occur when multiple bites or stings have been inflicted so systemic administration of antibiotics may be needed for a specific period of time
  • For internal irritation, recommendations may be made to use gastric protectants to alleviate internal discomforts
  • If there are muzzle lesions which are more progressed, a feeding tube may be placed to provide appropriate nutrition for the equine while it heals - this may also be needed if the horse suffers from persistent depression

  • Intensive eye treatments for any “melting” corneal ulcers - this may require administration of special eye solutions every 2 to 3 hours around the clock to save the horse’s eye

The sooner that medical care and appropriate treatment are begun, the better the survival rate is for the horse. Assuming the equine was reasonably healthy before the fire ant bites, you can assume there will be a good recovery if appropriate care and treatment are provided in a timely manner. Be sure to take an extra look around that pasture or even in the barnyard to locate any fire ant mounds. Treat them as soon as you find them and avoid putting your foals and older, sicker horses in those areas in which the mounds are frequently found.

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Fire Ant Bites Questions and Advice from Veterinary Professionals




Stock hors


13 Years


Moderate condition


0 found helpful


Moderate condition

Has Symptoms

Red Bloody Itchy Scabby Around Out

Hello my 13 year old stock horse paint got bit bye a poppy joe ant on his dick 🐜 about 4months ago and I wasn’t a problem but the past month it has gotten really red and swollen and flyblown

May 7, 2018

Chief's Owner


Dr. Michele K. DVM


1611 Recommendations

Whether the area on Chief's penis or prepuce is related to the any bite or not, he needs to be seen by a veterinarian to look at the area, determine what might be going on at this point, and get treatment for him, as that sounds quite painful.

May 7, 2018