Many horse owners are used to treating minor injuries and diseases, but when it comes to treating equine eye problems, the best advice from veterinarians is, "Don't."
According to veterinarians at UC Davis, the most common eye problems in horses fall into the following categories:
- Traumatic injuries
- Corneal disorders
- Inflammation inside the eye (uveitis)
- Cancer on or around the eye
- Cataracts
Traumatic injuries to horse's eyes range from superficial abrasions to severe lacerations that affect the eye structure. Eyelid abrasions and lacerations are usually obvious and superficial damage may be given first aid treatment.
Deeper lacerations that cause squinting, tearing, discharge of mucous or blood require immediate attention from a veterinarian and it is recommended that horses receive tetanus prophylaxis and topical and systemic antibiotics to prevent infection in addition to prompt repair of the damaged eye structure by a veterinarian, or in serious cases, an equine ophthalmologist.
Foreign objects such as dust, sand, or plant material that becomes lodged under the horse's eyelids may be flushed with water or saline solution, but any foreign object that pierces the eye ball should not be removed and needs the immediate attention of a veterinarian since microsurgery may be required to remove the object without damaging the eye further.
Corneal disorders or damage usually manifest as a painful eye with excessive tearing and resistance on the part of the horse to any examination of the eye area.
Corneal ulcers require immediate attention and care by a veterinarian to prevent blindness.
Inflammation inside the eye including uveitis, also known as moon blindness, and other conditions manifesting as inflammation are often recurring and the severity of the signs and frequency vary greatly among individual horses.
In all cases of inflammation, proper diagnosis and treatment by a veterinarian is crucial to preventing further damage and healing the eye.
The most common cancer affecting the eyes of equines is squamous cell carcinoma. These tumors occur on the surface of the eye, on the third eyelid, and within the eye. The masses have a wart-like appearance and are often readily visible.
Other types of cancer such as sarcoids and melanomas can also affect the eye and eye area. If diagnosed and treated early by surgical removal and proper treatment, most cancers do not have a lasting effect on the health of the horse.
Cataracts occur when the lens of the eye becomes opaque. Cataracts are usually progressive and result in visual loss over time. Foals are sometimes born with cataracts.
Removal of cataracts by a veterinarian as soon as possible usually restores the sight of the horse, although the horse will be far-sighted and unable to see things up close. Most horses that have cataracts removed go on to live fully productive lives.
Since the eye is an complex and delicate organ, all conditions related to the eye and its surrounding structure should be referred to an experienced equine veterinarian.