Bright sunshine can be a great thing. However it can also cause eye issues in horses. It’s important to ensure that your horse has adequate UV protection from the sun.

Sun and it’s warmth in the summer can cause a few issues;

  • Uveitis
  • Conjunctivitis
  • Ulcers

Uveitis is an inflammation of the uvea of the eye. This is a serious eye condition and should be treated as an emergency. This usually presents with a closed eyelid, tear staining and corneal oedema usually around the cornea but occasionally across it. Uveitis can also occur secondary to things like ulcers and trauma. Uveitis is also known, in its chronic form, as moon blindness and appaloosa breeds are more commonly affected. Chronic uveitis (more than 2 episodes in a year) can lead to retinal damage at the back of the eye and blindness. Therefore it is important to not ignore sore eyes and get them examined and treated by your vet ASAP.


This is often caused by fly’s feeding on tears and debris on and around the eye. It is most commonly seen in the summer months. UV masks will prevent fly’s from landing and feeding around the eyes therefore minimising the issues of catching conjunctivitis. The clinical signs are similar to other eye problems; closed swollen eye, tear staining, and red and swollen conjunctiva. Prompt treatment including staining to ensure there are no ulcers is important.


These can be a follow on from untreated conjunctivitis or can be the original cause of Uveitis. Ulcers are damage to the cornea which is the covering at the front of the eyeball. If it becomes torn due to a stab injury from thorny bushes, scratched when horses are hedge foraging, this can if left untreated lead to the loss of the eye.

Clinical signs; swollen eye, closed eye, tear staining, or obvious injury’s to the outside of the eye. Prompt veterinary assistance should be sought in these cases.


Providing protection for your horses eyes when it is out in the field is important. A good UV mask is vital as this will not only protect the eyes from the sun but will also protect them from insects.

All eye issues should be checked out as soon as possible by a vet. Issues with this organ would be classed as seriously as a colic in our book. The sooner you get them checked out the better the outcome will be.