equine metabolic syndrome | Horse Racing Free Tips

Ask the Expert: Fall Grazing

Owners and caretakers of metabolically challenges horses are often aware of the health hazards ingesting lots of fresh, spring grass can bring on their charges, but grazing horses on lush pastures in the fall is fraught with its own set of perils.

Frost damaged pastures can have higher concentrations of nonstructural carbohydrates, leading to an increase in the potential for founder and colic, especially in horses diagnosed with or prone to obesity, laminitis, Cushings disease and Equine Metabolic Syndrome. To help prevent these health issues, at-risk horse owners should wait up to a week before turning horses back onto a pasture after a killing frost. Subsequent frosts are not a concern as the pasture plants were killed during the ﬁrst frost.

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Why do nonstructural carbohydrates increase during the fall? During the day, plants carry out the process of photosynthesis. In this process, they make carbohydrates as an energy source for the plant. A second process, respiration, is carried out when the plants use up the carbohydrates they produce during the night for energy. Plant respiration slows down when temperatures are near freezing. As a result, the plants hold their carbohydrates overnight. Freezing can stop respiration and lock the carbohydrates in the plant for over a week. Thus, plants tend to contain more carbohydrates in colder temperatures or after a frost. Often, horses will prefer forages after a frost due to the higher carbohydrates levels.

Hoof Abscesses: A Sign Of Something More Sinister?

A horse with an abscess in his hoof can be startling to see he: He may be so painful he's loath to bear any weight on the affected limb, making horse owners fear a broken leg. One abscess can be time consuming and frustrating to heal, but a horse that develops multiple abscesses in different feet may have more going on than simply poor hoof condition.

Hoof abscesses are fluid-filled cavities under the sole or the hoof wall. They can be caused by sole bruising, puncture wounds or hoof cracks. Though some abscesses are only uncovered by the farrier during routine trimming—never causing the horse any discomfort—others are extremely painful. Abscesses can drain on their own, either down through the bottom of the hoof or up through the coronary band, or a drainage channel may have to be cut to offer the horse relief.

There are many concoctions for hoof abscesses, from veterinary-prescribed products to home remedies. Most products focus on drawing the material out of the abscess. Antibiotics are often not needed, but pain medication is essential to provide relief to the horse and prevent harm to the other hooves from bearing excess weight.

If an abscess doesn't begin to heal in a few weeks, a foreign body may be trapped inside the hoof, like a splinter or nail—or even a bone chip. A horse that is experiencing abscesses that don't heal well in multiple feet most likely has something else wrong and the abscesses are secondary.

Metabolic issues may cause a horse to have multiple of abscesses that don't heal well. Cushing's disease and equine metabolic syndrome (EMS) can cause laminitis, which can predispose a horse to abscesses. A veterinarian can run bloodwork to determine if a horse has either of these conditions and if they are the cause of the abscesses. Once the underlying conditions are controlled and hoof damage is addressed, the abscesses should decrease in both frequency and severity.

Equine Metabolic Syndrome: A Horse Health Enigma

Similar to other companion animals, obesity in horses is common—it's estimated that between 20 and 70 percent of horses are overweight. Ponies have the highest risk of becoming overweight, followed by cob-type horses.

Obesity is also one of the most prevalent health conditions in humans.; it's associated with premature mortality, metabolic dysfunction and a myriad of health conditions. In horses, obesity-induced conditions include laminitis. Because of this, obesity is important to both human and equine medicine.

Drs. Natalie Wallis and Eleanor Raffan note that obesity regulation can be disrupted by both genetic and environmental factors. The heritability of obesity is high in humans and lab animals, with evidence showing the same in companion animals.

Laminitis is of significant concern as it is such a devastating disease. The risk factors that link obesity and laminitis are collectively called equine metabolic syndrome (EMS). EMS is defined as insulin dysregulation. Insulin resistance is common in EMS, but it's rare for horses and ponies to actually become diabetic.

Add to that discovery that not all overweight equines develop EMS, and EMS doesn't always cause laminitis. Last but not least, not all horses that have EMS are overweight. These paradoxes exist across breeds and between individuals, similar to humans, where there is variability between individuals and between ethnic groups.

The scientists concluded that obesity is a health concern of both humans and horses, and more research is needed on the molecular basis of obesity and associated metabolic conditions. They also note that veterinarians have much to learn about obesity from human genetics and laboratory animal models. They hope that by using both of these, animal studies will be fast tracked

Read the review here.