Many readers have asked about dealing with a blind horse. Just like humans, horses can suffer from blindness. I've speculated that they may have other vision problems too, like far or near sightedness, problems with depth perception and other similar eye problems that may account for why some are spooky, get nervous under different lighting conditions or refuse to jump. Certainly, we know that they suffer from the vision maladies of old age just as we do. Very occasionally a foal is born blind or blindness occurs as a result of injury or disease.
It's important to understand horses and how vitally important vision was to their survival. While we probably underestimate how the horse uses its sense of smell and we understand they're hearing is very keen, it's vision may be its most important sense. Horses have both monocular and binocular vision allowing them to see into the distance and focus to the sides and rear better than we can. And they can see better in low light than we do. Because of the position of their eyes on the sides of their head they can see almost all the way around except for the very front and back. This incredible range of vision was very important to their survival in the wild. They needed to see predators a long way off and they needed to be aware of their path as they fled to escape predators. Despite this, however, many people report that blind horses adapt remarkably well.
Even though horses have been domesticated for thousands of years, that is really only a very short time on their evolutionary path and not long enough lose the flight response that served them so well in the wild. So we have to be sensitive to how stressful it is for a horse to be without one of the senses so essential to its survival.Some people feel that instead of fleeing, a blind horse is more likely to 'freeze'.
When it comes to keeping a blind horse from the time it is a foal, we need to consider two things: its security and our safety. To keep a blind horse for the next twenty or more years is a huge responsibility. How does one keep a blind, thousand-pound animal with a very keen flight response and the other animals and people around it safe as possible? The question becomes controversial with many people saying euthanasia is best. Safety, costs and the stress of being blind are often valid arguments against keeping a blind horse. Others argue that the animal deserves a chance. There are some cases where the choice is obvious. A horse with "recurrent uveitis" often experience extreme pain when the condition flares up. Some people, on deciding that they could not stand to see their companions in pain, make the heart-rending decision to have the horse euthanized.
In one case the owners of a blind foal built a special paddock with distinctive footing bordering the inside perimeter of the paddock so the foal would know when it was getting close to the fence. Of course, feed and water will always need to be placed in the same spot so it was easily found. Careful handling would be needed to ensure the horse doesn't hurt itself or someone else as they are led through doors, gates and into stalls. And because any horse can panic when it finds itself in a scary situation, great care has to be taken to ensure those situations don't happen--such as being chased by a dog, frightened by unexpected noises, getting caught on a bit of twine or having a turn out blanket slip.
Many readers have shared stories of blind horses living with companion horses who helped guide them through familiar pastures. Some people have mentioned that they talk constantly or sing when in their blind horse's presence so the horse always knows where they are. Keeping the surroundings and handling techniques consistent is important. Often, fencing that is relatively safe for the animal to bump into makes sense. They also need to be kept with a horse who will not harass them. Any pasture companions need to be chosen carefully, and a lot of care needs to be taken when introducing new horses to the herd.
Blind horses can be ridden. Most of these horses are very well-trained and obedient individuals that are ridden in closely controlled environments. The rider would need to be very focused as they are the eyes for both. Obviously, some riders will be more suited to looking after a blind horse than others. Again, owners of blind horses feel safe and help their horses adapt to their situation.
If owning a horse is a huge responsibility, owning a blind horse magnifies that responsibility. Not all horses will react the same to their condition, just as not all owners will react the same. I think the answer is to do the very best we can and when life becomes a burden for the horse, do the heart-wrenching but humane thing.