Owning a horse over his lifetime can be rewarding, but be prepared for specific costs related to his care

In barns across America horse owners are talking about their senior horses. They’re posting photos of them on social media platforms and asking questions about their care in online forums. Meanwhile, veterinarians are noticing an increase in senior patients in their practices, and researchers are discovering an upward trend in senior horse population numbers.

With all the old horses out there, it’s important to recognize the financial obligation involved with owning one, because, as horses age, health care needs and their cost can increase depending on what conditions arise. Armed with an understanding of the array of health problems that can crop up and how to monitor for and manage them, owners can mitigate the costs and enjoy their senior horses well into their golden years.

In this article we’ll review senior horse research studies and hear from veterinarians about what conditions these horses face and how husbandry requirements change across their life span.

Defining Old Age

First things first: What is a senior horse? Mary Rose Paradis, DVM, MS, Dipl. ACVIM, associate professor emerita at Tufts University’s Cummings School of Veterinary Medicine, in North Grafton, Massachusetts, says researchers around the world disagree on the age a horse is considered old.

Various researchers in England and Australia have completed studies with senior horses starting at age 15, while others have used horses age 20 and older.

Paradis has been studying younger horses and comparing their health data to that of older horses, looking for trends in disease progression. In one of her studies she surveyed U.S. owners, asking them when they thought their horses were starting to show signs of aging—the average response was 23. Researchers in England and Australia reported seeing early degenerative changes most frequently around 18 to 19 in some, but not all, study horses.

As a guideline, Paradis suggests considering your horse aging around 18 to 20 years and having your veterinarian get health baselines for future reference.

Are Horses Living Longer?

Paradis looked at age demographics in a 2003 study she completed with Margaret Brosnahan, DVM, PhD, Dipl. ACVIM, a clinical assistant professor at Midwestern University, in Glendale, Arizona. They found that the percentage of horses older than 20 in the university’s annual caseload increased from 2.2% in 1989 to 12.5% in 1999—an almost sixfold increase over a decade.

While Paradis studies horses within a hospital setting, the National Animal Health Monitoring System (NAHMS) surveys horse owners, industry stakeholders, and government officials periodically to gain an overview of the horse industry based on responses from farm owners with more than five horses. Paradis says NAHMS results likely underestimate older horse numbers because many retired horses live on smaller farms.

In its 1998 study the NAHMS program unit found that 7.5% of U.S. horses were 20 or older, while in 2015 it found that 11.4% of U.S. horses were 20 or older. Of that 11.4%, 1.5% were 30 or older. This could lead to today’s supposition that horses are living longer.   

Leading Senior Horse Health Issues

When we think about the top senior horse health problems, we need to consider whether a condition is truly one of only older horses or whether it’s a disease that has worsened over time and appears more prominently in old age.

“I think the biggest health issue is the fact that we hardly ever see one thing in isolation,” says Ann Dwyer, DVM, a private equine practitioner at Genesee Valley Equine Clinic, in Scottsville, New York. “When you are older, every single system in your body has undergone the changes that the years bring.”

Paradis says older horses are usually seen for veterinary care because of the gastrointestinal, musculoskeletal, and respiratory systems.

Endocrine Issues

Paradis says the disease most commonly associated with old age in the horse is pituitary pars intermedia dysfunction (PPID), commonly known as equine Cushing’s disease. While horses as young as 5-7 can have PPID, she says a large percentage of senior horses develop it, as risk increases with age. This incurable but treatable disorder of the pituitary gland’s pars intermedia is characterized by excessive hair coat, delayed shedding, muscle wasting, abnormal fat distribution, laminitis, recurrent infections, and more.

Musculoskeletal Issues

Dwyer sees many musculoskeletal conditions in older horses, usually from a combination of arthritis and soft tissue diseases such as tendonitis or desmitis (tendon or ligament inflammation, respectively).

Musculoskeletal problems were the second-most-common problem reported in the Brosnahan study. Of the horses seen by university veterinarians for lameness, 37.5% had the hoof disease laminitis (mostly secondary to PPID, she says), while 55% had lameness classified as degenerative disease.

Paradis says some older horses might experience progressive degeneration of the suspensory ligaments (which attach at the top/back of the cannon bone, split two-thirds of the way down the cannon, and attached to the sesamoids) in the hind limbs or be predisposed to osteochondral disease caused by stiff and brittle cartilage.

Gastrointestinal Issues

“Colic is always a big fear for the (owner of the) older horse,” says Paradis, who says 44% of small intestine problems found in her senior horse research were due to lipomas.

Dwyer sees many of these strangulating fatty tumors, which wrap around the small intestine and cut off circulation or cause an obstruction. She calls pedunculated lipomas (benign fatty masses originating from the mesentery, a membrane that supplies blood to the intestines and connects them to the body walls) one of the two most common life-threatening or -ending emergencies she sees in older horses. The other is severe arthritis in the spine or other skeletal region, which can prevent a horse from rising.

Dental Issues

In 2012 British researchers found that 95% of horses over 15 years of age have dental abnormalities; however, owners surveyed in that study reported that only 10% of the horses had dental disease.

These conditions include a smooth mouth (where the teeth are worn down to root level), wave mouth (unven wearing of the cheek teeth), step mouth (where one tooth is missing and the opposing tooth is overgrown), hooks (sharp points), shear mouth (malocclusion—when the jaws and teeth don’t align—producing marked enamel pointing), and equine odontoclastic tooth resorption and hypercementosis (EOTRH).

Dwyer says she’s concerned about the rise of EOTRH, which is a painful disease of the incisor and canine teeth. It often requires surgical extraction of multiple teeth to restore a horse’s comfort.

Paradis says dental disease probably plays a large role in the incidence of large colon impaction and esophageal choke in older horses. Dental issues often prevent horses from chewing and digesting feed properly, which can lead to these and other conditions, along with weight loss.

Eye Issues

Two ocular conditions that are part of the eye’s normal aging process are cataracts and senile retinopathy (age-related retina damage), says Fernando Malalana, DVM, Dipl. ECEIM, FHEA, MRCVS, RCVS, European specialist in equine internal medicine at the University of Liverpool Equine Hospital, in England. However, other eye conditions relate to a lifetime of accumulated damage from ongoing inflammation inside the eye, he says. Some can be halted if owners pick up on signs early and seek proper treatment. Other conditions, such as recurrent uveitis or glaucoma, might progress to the point horses need long-term medication and/or surgery.

Dwyer estimates that 1-2% of her practice population loses vision in one or both eyes at some point. “By the time you get to an old horse population, you’re going to see a lot of blind or partially blind older horses,” she says. “But now a lot more people are maintaining blind horses, and many of those horses still have productive lives.”

Heart Issues

Paradis says it’s important for veterinarians to auscultate (listen with a stethoscope) the heart because older horses can develop heart murmurs if the aortic valve becomes leaky with age.

Dwyer also says it’s extremely common to find heart murmurs in aged horses but, in her experience, it’s rare for them to be of clinical concern. However, if she observes clinical signs such as a cough, unusual swelling, or exercise intolerance in these horses, she refers them to an equine cardiologist for a workup.

Respiratory Issues

When Paradis studied respiratory issues among horses of all ages, she found no difference in their pulmonary function or in lung fluid cytology (microscopic examination of sampled cells), meaning respiratory issues in older horses are not a result of aging lungs.

“If your older horse is having breathing problems, it’s probably due to disease, not just because he is old,” she says. “If you have an older horse with a cough or increased respiratory rate, it’s probably because they have inflammatory airway disease (IAD, a mild condition usually seen in younger equine athletes), and you can treat that. Whereas if it was an aging change, as the lungs started to get worse, there would be nothing you could do.”

Dwyer adds that heaves (now known as equine asthma, a more severe, chronic condition than IAD) might become worse in affected horses as they age.

Cancer

Dwyer says cancer is rarer in horses than in dogs or people. However, she says melanomas that began in middle age (around 14-15 years old) might multiply or expand, causing obstructions that create serious issues such as hindered defecation. In addition, she sees squamous cell carcinomas of the penis in older males. 

What’s Involved in Senior Horse Care

Dwyer recommends owners help all horses live healthy lives, which includes designing diets to maintain proper weight. Owners should also schedule regular veterinary examinations that encompass all body systems. If veterinarians detect anything during an examination, owners can monitor or take steps to deal with the problem early on, says Dwyer.

This annual or biannual visit might include a sedated dental exam using a speculum; an eye exam; and geriatric blood screening, which could include a complete blood cell count and chemistry profile and/or tests for PPID.

The most commonly used tests for diagnosing and/or monitoring PPID include those for adrenocorticotropic hormone (ACTH, excessive levels of which can lead to PPID) and insulin levels. Insulin resistance—a decrease in tissue sensitivity to insulin—occurs in about one-third of PPID cases and increases risk for developing laminitis. Veterinarians might also perform an oral sugar test or the combined glucose-insulin test (CGIT) and, less frequently, the overnight dexamethasone suppression test (ODST).

“Blood testing, the type that we’re recommending, is not prohibitively expensive,” says Dwyer, adding that even though your veterinarian might recommend a variety of endocrine tests, individually they are relatively affordable.

Malalana also recommends scheduling at least one detailed eye examination a year to look for inflammatory conditions. “I would also advise owners to contact their vet immediately if they notice any ocular pain or ocular discharge,” he says. “Our research has suggested that eye discharge may be the only sign owners may notice when there is, in fact, something more serious going on with the eye.”

Paradis found during one survey that 10% of participants were still competing with 20-plus-year-old horses. “If you are going to compete an older horse,” says Paradis, “you need to think about the training. If they’ve been laid off, it’s going to take longer to get them to fitness than it would a younger horse.”

She also cautions against using senior horses as weekend warriors—riding them hard one day and then laying them up all week. “You want to make sure they are doing something every day,” she says.

Older horses that have problems chewing or digesting feed might need dietary changes. It’s important to work with your veterinarian because each horse has his own nutritional needs, especially if he has endocrine issues, an inability to maintain weight secondary to a disease, or an increased risk of laminitis.

Horse owners must be prepared to spend money on medication. In the Brosnahan study owners reported that 25% of old horses versus 6% of young horses were on regular medications. These were either for pain relief, recurrent airway obstruction, or PPID.

Brosnahan found that more than half of the older horses examined were also on a supplement, with 66% receiving a general vitamin/mineral supplement and 47% receiving a joint care supplement.

Many owners also find chiropractic treatment, acupuncture, and massage therapy to be helpful for managing various older horse conditions, says Paradis.

Realize that expenses can change as the horse ages. “The feed costs may change because processed foods for digestion are more expensive than less processed foods,” says Dwyer, referring to senior feeds on the market. “Sometimes farrier costs decrease slightly as horses go from being active competitors, where they need special shoes, to more barefoot management. What will go up will be oral care.”

In Summary

Dwyer sums up her senior horse care advice with the main thing she says owners need to think about: “If you are going to keep your horse into old age, be aware that old age can go well into the 30s,” she says. “No one can predict which issues that particular horse is going to have, but every geriatric horse is going to have some issues. Whatever those issues are, they will bring some expense over and above the normal husbandry costs.”