You most likely better know it as “moon blindness,” but periodic opthalmia, the most common cause of blindness in horses, has nothing to do with the phases of the moon.
The reason why horsemen used to attribute moon blindness to the phases of the moon is because of its tendency to appear suddenly, subside in about a week, and then come back. In fact, the reasons for moon blindness remain unknown, although there are a few hypotheses, which we’ll get to later.
Moon blindness is essentially the inflammation of the eye, and occurs most often in horses that are older than four years. While it may start in one eye, moon blindness eventually affects both eyes. Each recurrent attacks adds to the damage done.
What are the symptoms of moon blindness? Symptoms usually arrive suddenly, and include a severe sensitivity to light. The eyelid is often half shut, and sticky tears may be evident on the lower lid and cheek. The pupil does not dilate, the cornea is inflamed, and the blood vessels in the eye are clearly visible.
Following the initial phase of moon blindness, the horse’s cornea becomes cloudy and yellow at the edges. In two to three days, a cheesy substance builds up on the lower part of the pupil, which blocks the amount of light going into the eye. While these attacks will subside and the eye will appear to go back to normal, after each attack the eye will become a little more damaged. Atrophied eyeballs, thickened sclera, and eventually total blindness will occur in horses who have had several attacks.
As we stated earlier, no one really knows what causes moon blindness. The general consensus is that there may be a few reasons for the disease, including worm larvae, leptospirosis, allergic reaction, or riboflavin deficiency. What is known for sure is that the disease isn’t congenital or hereditary. So if your mare has moon blindness, you don’t have to worry about her passing it on to her offspring.
If you suspect your horse has moon blindness, call your vet right away. He or she will treat the disease by reducing inflammation through the use of topical corticosteroids. Anti inflammatories put into acrylic beads, which are then put in the sclerae, have also been used to prevent recurring bouts of moon blindness. Your horse should be kept in a dark stall throughout the course of the bout, as UV radiation tends to promote inflammation. If your horse must go outside or be exposed to daylight there are special ultraviolet blocking masks that he can wear to prevent exposure.
Unfortunately, there’s little hope that a horse with moon blindness won’t end up blind. The best thing you can do is treat the bouts of moon blindness quickly and aggressively with the goal of preserving your horse’s eyesight for as long as possible.
For more great equine resources please visit our links below and make sure to bookmark them, so you can visit often!
Thanks
Author Resource:-
Ron Petracek was raised in Southern Idaho with horses and the great outdoors. With this continued passion He now shares through a a vast equine network. Learn more by clicking the links below. Http://www.Horsechitchat.com/network.php or Http://www.equineinternet.com and view these great sites.
![[Valid RSS feed]](/images/icon_Rss.png "XML Feed For RSS"){kind=icon}
Category Rss Feed
Print This Article
Add To Favorites
