painful | Horse Racing Free Tips

The Plants A Horse Eats May Cause Sun Sensitivity

A horse with pink skin that blisters and peels may be having a painful reaction to sun exposure – but it may not be sunburn, as many would assume. Instead of overexposure to ultraviolet rays, this reaction takes place internally — photosensitivity occurs when horses with large white patches of skin graze on Saint John's Wort or alsike clover. The photodynamic compound in the plants circulates in the blood. When the compound comes close to pink skin and is exposed to the sun's UV rays, a chemical reaction occurs that damages tissues.

Secondary photosensitivity occurs when a horse's liver is damaged and unable to filter the toxin from the bloodstream, causing the same reaction.

In photosensitive horses, the skin on any white area of their body can blister, including on their face, legs or body. After the blisters, tight scabs will form. These scabs eventually peel away in a lengthy, painful process. Though horses can be afflicted with all sorts of skin disorders, photosensitivity is an exceptionally painful one.

If crusts appear on the horse's skin, it's imperative to identify if they are only located on white markings. If the crusts cross a border into darker hair, photosensitivity is most likely not the culprit. If there's any question, a veterinarian should be called for the best course of treatment.

Affected horses are often removed from fields that may contain phototoxic plants and kept indoors until the skin heals.

Is Cold Weather Hoof Pain Laminitis? Not Necessarily

Though cooler weather energizes most horses, dropping temperatures can be a pain—literally—for horses that develop hoof pain as temperatures drop. Though what is considered “too cold” can vary by horse, some horses become painful in temperatures just above freezing: 40 degrees F. Pain generally disappears as soon as the temperature rises above this threshold.

Though it's sometimes called “winter laminitis,” there's no evidence of inflammation and often no changes that can be discerned on an X-ray. The cause is a failure of the hoof to effectively respond to changes in circulation caused by the cold. This cold-induced pain is temporary, but can be significant.

In a healthy horse, cold temperatures will cause the blood flow to limbs and hooves to be reduced. Cold temperatures cause the arteriovenous shunts in the hooves to open and divert blood back to the horse's core to preserve body heat. This mechanism will also periodically close the shunts and send blood to the tissues so that oxygen and nutrient levels don't get too low.

This system doesn't work in horses that have cold-induced hoof pain; the tissues don't receive shunts open, but don't occasionally send adequate blood flow to the hooves.

Horses with cold-induced hoof pain can be assisted by blanketing them to help conserve body heat. Wrapping their legs can also help; lined shipping boots work well as they cover the heels and coronary band, preventing rain and snow from getting into the boots. Adding Jiaogulan, a Chinese herb, to an affected horse's diet may also help. Jiaogulan stimulates the production of nitric acid, which is turned into a potent vasodilator in the body.

Though painful, cold-weather hoof pain is temporary and can be managed to keep a horse more comfortable.

Equine Recurrent Uveitis And Appaloosas: What’s The Correlation?

Every Appaloosa over the age of 12 should have an eye exam to ensure the horse isn't suffering from equine recurrent uveitis (ERU) or moon blindness, a disease that disproportionately affects the breed. As the disease progresses, it can lead to blindness.

A study by Drs. Sandmeyer, Nicole Kingsley, Cheryl Walder, Sheila Archer, Marina Leis, Rebecca Bellone and Bianca Bauer completed a retrospective study using horses that were referred to the Western College of Veterinary Medicine in Canada.The research team found that ERU occurred 13 percent more often in Apps than in other breeds; of all horses at the hospital who had ERU, Appaloosas made up 62.5 percent of the ERU cases.

The study team then had board-certified ophthalmologists examine 145 Appaloosas on 11 farms in Western Canada to determine what risk factors Appaloosas have that may be relevant to ERU development. They sought to study if coat pattern correlated at all with ERU risk: Specifically, if Appaloosas that had extensive white were more at risk to develop ERU.

Horses were categorized as having no signs or mild, moderate or severe signs of ERU. Of the 145 horses examined, 20 (14%) were confirmed with ERU. The research team determined that:

ERU occurred 11 percent of the time in horses with few spots; 29 percent of the time in Apps with white blankets and no spots (called snowcap); 15 percent in leopard apps, which are white with spots all over; 11 percent on Apps with a white rump that has spots and 13 percent of the time in Apps with no patterning over the topline
There was no association between gender or base coat color and ERU
Age is a significant risk factor; 12.3 years old being the mean age of affected horses. For each year older, the odds of ERU increased 1.15 times
The study did not find ERU in horses that had white-flecked coats, lace blankets or solid coloration that does not roan with age
Apps with leopard spotting are at increased risk for ERU
A common ancestor was identified in 83 percent of affected horses within eight generations, and five were inbred to that ancestor

The scientists determined that many horses have chronic, low-grade clinical signs of ERU that go undetected until the condition worsens. Because of this, it's imperative that owners of Appaloosas have their eyes checked yearly, specifically after 12 years old.