How can uveitis be recognized in horses?

December 1, 2022

Uveitis is an eye condition that is becoming increasingly common in horses. It is characterized by internal inflammation of the eye, which is particularly painful and, in many cases, recurrent. Although treatments are available, the main challenge is to prevent complications and relapses. It is the leading cause of blindness in horses.

Equine uveitis: protective masks and goggles

Uveitis, an inflammation of the uvea

The symptoms of uveitis vary depending on the intensity of the inflammatory episode, its stage of development, and its location in the eye. However, in most cases, the main symptom of uveitis is pain in the horse, with one eye closed and very sensitive to light.

Leptospirosis, one of the major causes of recurrent uveitis in horses

This disease, which can affect horses without showing any clinical signs or sometimes with just a simple fever, is an infection caused by bacteria. As the attacks continue, hence the name recurrent uveitis, a permanent change in the color of the iris, a more or less diffuse cataract, a deformed pupil, or a change in the size of the eyeball can be observed. It should be noted that with each new flare-up of uveitis, in addition to pain, the inflammation worsens the condition of the animal's eye and causes numerous sequelae. Lyme disease is also often the cause of recurrent equine uveitis.

You think your horse has uveitis

Uveitis is a serious condition that should not be taken lightly. Apart from vision loss or impairment, it is often the management of pain that becomes complicated in the long term and can be a real nightmare for the owner. Some horses are genetically predisposed, particularly Appaloosas. Age is not a discriminating factor. In most cases, the horse will only receive symptomatic treatment in the form of eye drops to relieve pain, reduce inflammation, and attempt to limit the after-effects. The horse should remain in the dark or away from light as much as possible. Whether your horse is suffering from a single attack or a recurrence, our products are designed to help you manage this problem and protect your horse's eyes as best as possible. They allow horses to continue living normally, both at work and at rest, while being protected from the elements and light. Their field of vision is preserved. If in doubt, do not hesitate to consult your veterinarian. The sooner you intervene, the less difficult the attack will be to manage.

> See also: Medication and surgical treatments for uveitis in horses

What size should I choose for my Equidiva mask/hat?

All measurements are approximate and are provided for informational purposes only.

Size guide - Premium or Helios mask

Using a tape measure (or a piece of string that you will measure afterwards), measure around your horse's head as shown in the photo:


Mask size Head circumference
XS - Shetland 84 cm
S - Pony 90 cm
M - Cob 94 cm
L - Full 100 cm
XL - XFull 110 cm
If your horse's head measurement falls between two sizes, we recommend choosing the larger of the two.



Size guide - Equivizor masks (Lightweight, Arso, Convalescence models)

For these masks, the main measurement is the width of your horse's forehead. To do this, you need to add together three measurements:

  1. Start at the outer corner of one eye and measure upwards at a slight angle to the middle of the forehead (measurement A).
  2. continue along the front of your horse(measurement B),
  3. Finish the measurement by directing the line slightly downward to the outer corner of the other eye (measurement C). This way, you will measure the widest part of your horse's forehead.

Add these 3 measurements (A+B+C) to obtain the size of your horse's forehead.

IMPORTANT: Do not measure directly from one eye to the other, as this will likely result in an inaccurate measurement.

equivizor mask measurements

Mask size Forehead size
XS - Shetland 7.5–8.7 inches
S - Pony 8.7–11.4 inches
M - Cob 11.5–13.5 inches
L - Full 13-14 inches
XL - XFull 15-17 inches


Size guide - Rambo mask

Take these 3 steps:


Size A B C
XS (large Shetland) 60 cm 84 cm 20 cm
S (pony) 70 cm 96 cm 9.5 inches
M (cob) 70 cm 96 cm 9.25 inches
L (full) 75 cm 105 cm 27 cm

If your horse is between sizes, we recommend choosing the smaller size.


Size guide - Equivet mask

Measure the distance between the center of the horse's two eyes:


Mask size Distance between the eyes
S - Pony 18 cm
M - Cob 21 cm
L - Full 9.5 inches
XL - XFull 26 cm


Size guide - eVysor glasses

The eVysor mask is available in one size. It is suitable forcob orfull horses. It can also sometimes fit large ponies (D ponies).
evysor measurement



Made a mistake? Exchanges are always possible, and we will process them as quickly as possible provided that you return the item to us intact within 14 days.
> See the return policy