Last Updated on March 24, 2022 by Fabiola L.
If you’ve ever had to deal with summer sores in horses, you’ll know what a problem these horrible lesions can be! Summer sores cause intense itching for the horse and can take a very long time to heal. Let’s find out everything you need to know about summer sores in horses!
What Are Summer Sores In Horses?
Summer sores in horses are also known as habronemiasis, granular dermatitis, and jack sores. They occur when the life cycle of the stomach worm is disrupted and the larvae become trapped in a wound on the horse’s skin. These larvae are unable to complete their life cycle and travel around the wound causing localized irritation.
Normally, these larvae would be deposited near the mouth of the horse, where they are then ingested and travel through the gastrointestinal tract. They then mature into worms and lay eggs, that are deposited in the horse’s droppings. These eggs hatch into larvae and are picked up by house flies, starting the cycle over again.
Stomach flies are relatively harmless when they complete their normal life cycle, but when the larvae are deposited in the wrong place they can become very problematic. The larvae are unable to turn into worms and work their way around the inside of the wound, causing irritation and itching. The horse will chew on the wound, making it worse and causing a persistent non-healing lesion.
What Are The Symptoms Of Summer Sores In Horses?
Summer sores are characterized as non-healing skin lesions, that are incredibly itchy. The chewing action of the horse prevents the wound from healing and also stimulates proud flesh to form. Proud flesh, also known as granulation tissue, is an overgrowth of pink, fleshy tissue that protrudes from the wound, making it impossible to heal.
Summer sores can appear anywhere where the horse has a wound on his body. However, flies tend to congregate in moist, warm areas, and this is where summer sores are more likely to occur. Common areas for summer sores include the corners of the eyes and lips, the genitals, and the lower abdomen.
The problem with summer sores is that the horse has a non-healing wound that can last for years. These lesions often get worse over time and cause a lot of irritation to the horse. They also attract flies, which can then cause more summer sores to develop.
A classic summer sore will have a shiny, greasy appearance, and you will see pinky blood-tinged fluid draining from the lesion. It is common to see yellowy-white rice-like material inside the wound, which is calcified tissue.
Summer sores normally appear in the spring and summer, when fly activity is at its worst. If left untreated, the sores will reduce in size during the winter, but reappear in the spring.
Best Treatment For Summer Sores In Horses
To treat summer sores in horses, we first need to kill the stomach worm larvae and then help the wound to heal. The best way to remove the stomach worm larvae is to worm the horse with an ivermectin or moxidectin deworming paste. These are the only two types of dewormer that are effective against the stomach worm larvae; other dewormers will not be effective. If the lesions are small and relatively new, a deworming treatment may be all that is needed to allow the summer sores to heal.
However, if the summer sores are itchy and inflamed, it is likely that the horse will have got into a cycle of chewing the lesion, preventing the wound from healing. In these cases, treatment of the wound will be necessary.
The best way to stop the horse from chewing is to alleviate the itching and irritation in the wound. Topical medication, such as glucocorticosteroid and DMSO, can ease inflammation. It may also be necessary to cover or wrap the lesions to prevent the horse from chewing.
In severe summer sores where proud flesh has developed, this may need to be removed surgically. Removal of this proud flesh will allow the edges of the wound to close over. In some cases, cryotherapy can be used to eliminate proud flesh.
The most important thing to remember if your horse has summer sores is to use effective fly control methods. This will help prevent new sores from forming elsewhere on the body. Fly repellents, summer fly rugs, and good barn hygiene standards will all help to reduce the number of flies around your horse.
So, as we have learned, summer sores in horses are also known as habronemiasis, granular dermatitis, and jack sores. They occur when the life cycle of the stomach worm is disrupted and the larvae become trapped in a wound on the horse’s skin. These larvae are unable to complete their life cycle and travel around the wound causing localized irritation.
We’d love to hear your thoughts on summer sores in horses! Have you got a horse that suffers from this persistent problem? Or maybe you’ve come across an innovative way to cure summer sores in horses? Leave a comment below and we’ll get back to you!
What Causes Summer Sores In Horses?
Summer sores in horses occur when the larvae of an equine stomach worm are deposited by house flies near to an open wound on the horse's body. The larvae cause irritation and localised inflammation, resulting in an itchy, oozing, persistent sore.
Where Do Summer Sores Appear In Horses?
Summers sores can appear on any part of the horse's body, but some areas are more likely to be affected than others. These include the limbs, especially the lower legs, the sheath, the eyes and face, and the under-belly.
How To Treat Ear Mites In Horses?
If you suspect that your horse has ear mites, your veterinarian will take scraping of the surface of the skin inside the ear to confirm the diagnosis. This will be examined through a microscope to look for ear mites.
Ear mites in horses are treated with medication that can only be obtained from your veterinary clinic. Effective treatments include a mixture of pyrethrin and ivermectin which is applied directly into the ear. An application of topical frontline can also be used to treat ear mites in horses.