Geriatric horses hold important place in society

By Bruce Connally, DVM, MS
Colorado State University

Horse care is changing in the United States, and some of the most dramatic evidence of that is the lifespan of our horses. Now it is common to see horses in their upper 20s and even into their 30s. Ponies may reach their 40s.

There are many reasons for this dramatic increase in longevity. In the past, if horses could not work, they were not usually kept on the farm. Today a horse may remain an important member of the family long after athletic soundness has diminished. It is these older horses that teach our grandchildren to ride and who provide a few moments of calm for us in this fast-paced world.

Our geriatric horses require a bit more care than their younger stable mates. Nutrition is the first area of concern. Older horses often do not utilize their feed as well as younger horses and may become thin. We may have to give the older horse a little more feed or a little better quality feed to maintain its body condition. There are also senior feeds that have been formulated to be easier for the older horse to digest. If the horses are fed in groups, an older horse may not be able to compete with younger pasture mates. Supplementing an older horse may allow it to remain in the herd.

The opposite may also occur in that older horses are often less active and may gain excess weight. Many older horses get retired to the pasture where exercise is limited but calories are not. Obesity adds stress to the feet and legs of horses, just like it does to people.

After 20 years of chewing hay, a horse's teeth may show some age also. Teeth may be worn short enough to make chewing ineffective or may be missing altogether. Other teeth may wear unevenly, resulting in large sharp points that cause pain when the horse eats. Annual dental exams and possible treatment provide an important adjunct to nutritional management of the older horse.

It is important not to blame teeth problems for all thin horses. Recent studies have shown that horses with very worn teeth are still able to grind their food effectively as long as the teeth are not causing pain.

Vaccinations are equally as important for older horses as they are for the youngsters. Older horses are less susceptible to influenza but require sleeping sickness, tetanus and West Nile boosters each year. Rabies is also becoming more of a concern on the eastern plains of Colorado. Geriatric horses often have good resistance to strangles, but infection is still possible in horses over 20 years of age.

One metabolic disease that is diagnosed frequently in older horses is Cushing's disease. Horses with Cushing's disease have increased cortisone in their blood as a result of a benign tumor in the pituitary gland at the base of the brain. These horses usually develop a long curly hair coat that does not shed off in the summer. They may sweat excessively, urinate excessively and appear somewhat sedated.

The most serious effect of this syndrome is laminitis (founder). Cushing's disease is not curable but may be treated with a drug formerly used in human patients for Parkinson's disease called Pergolide. This once-daily treatment can often control signs of Cushing's disease for several years.

Another condition that we see in older horses is equine metabolic syndrome. These are the easy keepers who seem to get fat regardless of their diet. By far the most devastating part of this syndrome is the tendency toward laminitis in their feet. This is why old horsemen used the term "grass founder" to describe the syndrome. Exercise, weight loss and some restriction of carbohydrates in the diet are the only effective treatments for equine metabolic syndrome.

Older horses, just like older people, tend to develop orthopedic disease. The cartilage wears out and arthritis develops in joints that are used a lot. While we cannot reverse the aging process, we can help minimize its effect on the horse. Keeping extra weight off and performing regular hoof care reduces strain on bones and joints. Exercise not only increases flexibility but also decreases pain from arthritis. Anti-inflammatory drugs are helpful as well. Drugs such as phenylbutazone can be abused, but appropriate use can make an older horse much more comfortable and even functional again.

Geriatric horses have become important in our society. For some of us who do not ride frequently, or for children learning to ride, the training and experience of an older horse are invaluable. If we take care of these old friends they can serve us happily for many years.

Dr. Connally is an assistant professor of the equine field service at Colorado State University's James L. Voss Veterinary Teaching Hospital. He provides ambulatory services for equine patients in northern Colorado, including vaccinations and wellness care, lameness examination and emergency treatment. He can be reached at 970-491-4471.