Rain rot in horses is a bacterial skin disease that is caused by the bacteria known as Dermatophilus congolensis. It manifests as groups of crusty scabs that peel off and leave unsightly bare patches on the skin. This bacterial infection is caused by exposure to rain and usually appears along the horse’s topline head and neck. It is unusual to find rain rot on a horse’s undersides or legs. Keep reading to learn more about rain rot in horses home remedies, including the video below.
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How Does Rain Rot Happen?
This infection usually occurs in areas that tend to have high humidity and high temperatures along with heavy rainfall. It is quite common in the southern US during the winter.
It is also far more common to see this infection on horses who are in poor condition and/or have compromised immune systems.
These bacterial spores are not able to penetrate the skin of a healthy horse, except in situations in which the horse has been wounded or has an abrasion or scrape.
Excessive insect bites and the itching that they cause also create an opening for this bacteria to enter.
It’s easy to mistake rain rot for a fungal infection because the symptoms look quite similar. Additionally, fungal infections are also brought on by damp, muggy conditions.
It’s important to get a proper diagnosis right from the start because treating for a fungal infection will do nothing to address a bacterial infection.
A veterinarian can make a positive diagnosis. Sometimes this requires a skin scraping and a culture, but most of the time your vet will be able to recognize rain rot for what it is.
How Do Rain Rot Symptoms Develop?
Once the bacteria has penetrated the horse’s skin, the immune system begins producing extra proteins and white blood cells.
These accumulate and form pustules on the horse’s skin. You may not be able to see them, but if you run your hand over the affected area, you will feel the small lumps.
With time, the skin underneath the pustules begins dying. This leaves clumps of dead skin cells which become scabs. The horse’s hair pokes through these scabs like paint brush bristles, so they are often called paintbrush lesions.
The development of these lesions causes the horse’s skin to become itchy, sensitive and dry. When he scratches, the skin becomes even more damaged and the bacteria spreads.
You may see small individual lesions all over your horse’s back and topside, or the lesions may cluster in clumps.
This leaves broad areas of bare, red, raw skin. If the weather has cleared up and the horse is healthy, this new skin will heal and the problem will be solved.
Unfortunately, if the conditions that caused the horse to develop rain rot in the first place continue, the new skin will be reinfected and the problem will begin again.
Horses kept in poor condition, and/or those that are in poor physical shape may experience rain rot infections over and over again for long periods of time. This can result in a secondary if infection, such as Staphylococcal folliculitis.
Severely neglected horses kept in very poor conditions can develop systemic infections in which they lose most of their hair, lose weight and experience pain in high fever.
What Are Some Good Rain Rot Home Remedies?
There are a number of different home remedies you can use to treat rain rot one of the simplest is also recommended by veterinarians. Here’s how to make it.
Rain Rot Remedy #1
In a 3 gallon bucket combine:
- 16 ounces of mineral oil or baby oil
- 16 ounces of 3% hydrogen peroxide
- Half an ounce of tincture of iodine
Adjust measurements as needed to make only the amount you will use at once. You cannot store this concoction because the hydrogen peroxide will cause it to bubble and explode.
Sponge this concoction liberally over the affected areas on your horse and the surrounding areas just for good measure.
Leave the mixture in place overnight to help soften the scabs and lift them. The mineral oil or baby oil will also lubricate and soothe your horse’s skin, while the tincture of iodine kills off the bacteria.
After twenty-four hours have passed, give your horse a thorough shampooing using a mild shampoo such as Doctor Bronner’s Castile soap.
If the day is dry and warm, turn your horse out into a clean, sunny location with good grass on the ground so that if he rolls he won’t become covered with mud.
Rain Rot Remedy #2
Another recipe along similar lines simply involves mixing equal parts baby oil and brand name Listerine and following the same instructions. This can also work, but the isopropyl alcohol contained in Listerine can be harsh on the skin.
Some people like to use full strength Listerine as a spray-on preventative after treatment. This may work to help prevent the bacteria from taking hold again, but remember that the alcohol in Listerine can be hard on your horse’s skin and hair.
Rain Rot Remedy #3
If you would like to try this, you’ll need to wash the affected areas thoroughly with Betadine scrub and then apply a paste made up of equal parts:
- Hydrocortisone 1% Ointment
- Triple Antibiotic Ointment
- Nystatin Anti-Fungal Ointment
Mix these together and apply to the affected areas after washing with Betadine.
Do this daily for several days until the sores have healed thoroughly. If you wish, you can follow-up by sprinkling the areas with an athlete’s foot powder.
While anecdotal evidence indicates that this treatment works, it’s important to remember that rain rot is not caused by fungus, so all of the ingredients used in this treatment which are intended to fight fungus (i.e. athlete’s foot) are actually ineffective and probably waste of money.
How To Treat Rain Rot
What Can You Do To Prevent Rain Rot?
To prevent your horse from getting rain rot, be sure that he can always come in out of the rain if he needs to.
During the wintertime, if he wears a blanket, be sure to take it off and give him a good brushing every day so that his skin can air out. Keep his blanket clean.
Store your tack properly with the blanket turned upside down on top of the saddle so that it can air out when not in use.
Likewise, keep your saddle stored in such a way that air can get to the underside and dry out the fleece or other material.
Never allow your horse to stay wet for a long period of time. Scrape off excess water after bathing and don’t turn him out until his coat is completely dry.
During warm weather, be sure to use insect repellent on a regular basis to prevent having your horse’s skin become itchy and compromised.
You can also protect your horse from biting flies by using a fly sheet during the spring and summer.
Be sure your horse gets plenty of turnout because exposure to sunshine will help keep his skin healthy. He should have at least an hour a day of free, turnout time.
Planting natural insect repellent plants around your barn and property can also help keep flies under control. This in turn keeps rain rot under control. Some good choices include:
- Scented Geraniums
Be sure to keep your manure pile turned and covered to discourage the breeding of flies and other parasites. Rotate your pasture frequently as this also helps keep parasites under control.
Keep your horses off muddy ground as they may tend to roll, and some people believe that the bacteria that causes rain rot lives in the soil. A wet, muddy horse is far more likely to develop rain rot.
Take a holistic approach to rain rot by feeding a healthy and varied diet that provides your horse with plenty of immune boosting nutrients and antioxidants. Keep your horse’s immune system strong by avoiding stress.
Frequently Asked Questions
Begin by exposing the infected skin by removing the scabs. After you’ve cleared off all the scabs, you can sterilize the infected skin by giving your horse a bath using an antimicrobial shampoo. Remember to dry your horse thoroughly after bathing.
Rather than picking, brushing or scraping them off, simply spray them with an anti-bacterial spray a day or two before bathing your horse. They should fall off naturally without any potentially painful actions. Once they are out of the way, bathe your horse as described above.
It typically takes about three weeks for the infection to heal on its own. This will happen more quickly if the weather dries up. Continued wet weather extends the amount of time the infection persists.
If you can provide antibiotic injections as soon as you see the horse’s coat begin to raise (before scabs occur) you can prevent rain rot from taking hold and causing hair loss.
Provide your horse with good shelter from harsh weather. Groom your horse daily to prevent dirt from building up under the hair coat. A dirty coat provides an ideal setting for bacteria to build up and multiply.