The pleasures and pitfalls of caring for very old horses

“You can’t help getting older, but you don’t have to get old.” The immortal words of late comedian George Burns might very well apply to our horses. With their elevation in status from work animals to companions, horses’ “average” lifespan has increased dramatically over the past several decades.

“Many horses continue to lead active and productive lives well into their 20s and 30s,” says Jo Ireland, BVMS, PhD, CertAVP(EM), MRCVS, a lecturer in equine practice at the University of Liverpool’s School of Veterinary Science, in Leahurst, U.K.

“Albeit rare, reports of horses living to be 50 do exist.

“While some (owners) focus on age in years, others instead assess their horse’s physiologic age and base aging on functionality and the presence or absence of age-related diseases,” she adds.

Burns’ words of wisdom aside, Ireland attests that horses over 15 years are generally classified as old, whereas those 30 and above are very old. In human medicine, a common term for this population is “late elderly.”

The number of horses surviving 30 years or more is, not surprisingly, small. Current estimates suggest that only 2.2% of all horses and ponies in the U.K., for instance, are over 30.

In this article we’ll review the unique needs of very old horses. We’ll also meet five horses beyond 30 with age-related ailments.

Elderly Horses’ Aches and Pains

To understand how to best support seniors, we first need to learn which body systems mostly commonly develop problems. Catherine McGowan, BVSc, MACVSc, Dipl. EIM, ECEIM, FRCVS, professor and director of the equine division at the University of Liverpool, says clinicians collecting case data at referral centers tend to report acute conditions such as colic, whereas veterinarians conducting field-based studies tend to note more chronic conditions.

Results from British and Australian field studies show the leading causes of morbidity (illness) in horses 15 years and older as:

1. Dental abnormalities, including cheek teeth issues, diastemata (gaps between teeth), excessive wear, and focal overgrowths, in 95-96% of examined older horses;
2. Dermatological abnormalities such as hypertrichiosis (long wavy coat/failure to shed), skin tumors, and Culicoides (biting midges) hypersensitivity in 40-71%;
3. Ophthalmic lesions such as cataracts, vitreous degeneration, and senile retinopathy in 88-94%;
4. Cardiac abnormalities, including murmurs, in 25-43%;
5. Nasal discharge or breathing abnormalities in 7-22%;
6. Lameness in up to 50%, although up to 80% had hoof abnormalities; and
7. Pituitary pars intermedia dysfunction (PPID) in 21.2%.

In a separate study Ireland performed exams on horses 30-plus years old to identify leading morbidities in this population. She found that:

• 100% of the horses had dental and ocular abnormalities;
• More than three quarters (77%) were lame; and
• Horses experienced an increased prevalence of dermatological, cardiac, and respiratory abnormalities.

Upon comparing the horses in the 15-plus and over-30 groups, Ireland found that only 10% of the very old horses were overweight, versus 26% of the 15-plus. Fifteen percent were underweight, com pared to only 4% of the 15-plus horses.

Researchers have shown that owners tend to underreport medical conditions, particularly chronic ones, in their horses. To be fair, many conditions in older horses are difficult to detect without a veterinary exam, particularly dental, ophthalmic, cardiac, and respiratory issues.

Further, in her research McGowan recognized that what owners identify as major medical concerns in older horses does not necessarily match what veterinarians find on their examinations. For example, owners report weight loss/maintaining condition, arthritis and other causes of lameness, and dental care as the most common issues, which only scratch the surface of old horse morbidities.

Now that we know what commonly ails aged equids, let’s meet five super-seniors and learn about the issues they face.

Doug: Battling Dental Disease

Indeed, Doug, a gray 32-year-old Appaloosa, does not walk alone when it comes to dental disorders. Neil Townsend, MSc, BVSc, MRCVS, of Three Counties Equine Hospital, in Gloucestershire, U.K., says most of the dental issues we see in about 95% of geriatric horses stem from normal age-related changes. But they can be aggravated by dietary management and even excessive dental treatment early in life.

Doug’s recent dental exam revealed that his incisors don’t meet as snugly as they once did, potentially making it more challenging to grasp forage. His canine teeth have a notable amount of calculus (plaque), with a small fracture beginning to form on one. Farther back, his cheek teeth have sharp points. Some are unstable due to lack of reserve crown— this means he’s essentially running out of tooth (equine teeth erupt gradually over time but are a finite length).

“During routine dental treatments, those sharp points on cheek teeth must still be removed to avoid traumatizing soft tissues in the horse’s oral cavity, and the large array of age-related cheek teeth abnormalities must also be addressed,” says Townsend.

Other examples of senior horse cheek teeth abnormalities include smooth mouth (the teeth are worn down to root level), step mouth (overgrowth of the teeth opposite a lost or worn tooth), and shear mouth (the jaws and teeth don’t align).

Practitioners managing older mouths like Doug’s with multiple problems typically tackle the issues in a stepwise fashion. This means more frequent visits than what younger animals generally need.

“The ultimate goal is to ensure oral comfort and to maximize masticatory (chewing) ability,” says Townsend.

Xandria and Xander: Creaky but not Crippled

Is your horse having trouble with his get up and go, no longer loping up to the gate when you deliver supplementary feed and hay? Then it’s time to heed actor John Wagner’s advice: Don’t let aging get you down, it’s too hard to get back up.

“In a study of 69 horses 30 years and older, a staggering 77% was found to be lame at clinical examination, and almost 100% of those horses had a reduced range of motion in at least one joint,” says Paul René van Weeren, DVM, PhD, Dipl. ECVS, head of the Department of Clinical Sciences in Utrecht University’s Faculty of Veterinary Medicine, in the Netherlands.

Musculoskeletal diseases such as chronic joint disorders and the debilitating hoof disease laminitis were the principal reasons cited for euthanasia in approximately one-quarter of these geriatric horses.

Let’s take a look at our stately pair Xander and Xandria, pasturemates in their early 30s. Xandria is an off-track Thoroughbred who, like many retired athletes, suffers from osteoarthritis—the painful joint disease characterized by degeneration of the articular cartilage lining the ends of long bones. It often develops as a result of repeated microtrauma to the joint. Xandria’s owner had noticed mild to moderate lameness in both forelimbs when the 33-year-old mare meandered around the paddock. She also observed swelling in the front fetlocks. The vet noted that Xandria’s range of motion in those joints decreases with every visit.

Because articular cartilage cannot regenerate, the veterinarian’s goal is to keep the mare as comfortable as possible. Van Weeren says this includes a combination of intra-articular therapies, non-steroidal anti-inflammatory drugs, and oral joint health ­supplements.

“Management strategies falling into the category of ‘other,’ but not to be viewed as second-class recommendations, include weight management, appropriate shoeing, physiotherapy to optimize joint stability, and controlled exercise that does not reach the point of fatigue,” he says. 

For Xander, Xandria’s 31-year-old Quarter Horse companion, laminitis has been an on-and-off issue for several years. Because Xander has always been on the plump side and has suffered recurrent bouts of mild yet still painful laminitis, his veterinarian tested and confirmed that he has insulin dysregulation, the central feature of equine metabolic syndrome (EMS). Xander’s owner altered his diet to encourage weight loss and reduce nonstructural carbohydrate (e.g., concentrates, sweet feeds, lush pasture) intake. She also helped minimize bouts of laminitis (and, therefore, fatal progression of the disease) by ensuring Xander has routine farrier visits and veterinarian-prescribed medications for managing pain and EMS.

“Although chronic OA and laminitis aren’t typically viewed as life-threatening disorders, they are certainly disabling and, therefore, have important welfare issues in aged horses,” says van Weeren. “The pain present in both cases must be controlled, along with changes in management to keep the musculoskeletal systems as healthy as possible in this generation of horse.”

Patrick: Prince of PPID

Patrick, a 36-year-old Arabian cross, did not have the luck of the Irish but instead ended up getting PPID—as many aged Arabians and ponies do. This endocrine disorder affects an estimated 21.2% of horses 15 and older, as compared to 2.9% of the general equine population.

“The reason why many aged ponies and Arabians fall prey is that they tend to live longer, and PPID is well-associated with age,” says McGowan. “In a 2013 study I reported that the odds of developing PPID increased by 18% each year from 15 years of age. So by the time a horse is 36, then the luck of the Irish may well run out!”

Advancing age appears to be the main risk factor for PPID, says Ireland, adding that by the time a veterinarian first diagnoses the condition, most horses are around 21 years old.

“The good news for Patrick is that with appropriate treatment, such as oral pergolide medication and routine farriery, he can expect to live for several more years and perhaps up to another decade,” Ireland says. 

To enjoy those golden years, however, owners must recognize signs of disease in their horses and get a veterinarian’s diagnosis.

“Failure to recognize important signs of an underlying problem leaves a large number of horses undiagnosed and, therefore, untreated,” says McGowan. “Especially signs that were once (erroneously) considered to be normal signs of old age such as swayback (epaxial muscle wastage), a potbelly, and reduced exercise tolerance.”

She says owners also tend to overlook another hallmark sign of PPID, hypertrichiosis, because it occurs slowly over time. 

Victor: At Risk of Eye Infection

In one study Fernando Malalana, DVM, Dipl. ECEIM, FHEA, MRCVS, senior lecturer at the University of Liverpool, found that ocular abnormalities occur in approximately 94% of horses 15 years of age or older. The prevalence of ocular disease in horses over 30? 100%. He found, however, that only 3.5% of owners reported concerns regarding their horses’ eyes, and only 2.6% perceived eyesight as an important health issue.

This might be, at least partially, because few ocular conditions result in complete blindness. Plus, Malalana says only 5.5% of horses with diminished vision have a reduced menace response (veterinarians check for this by waving a hand while moving it rapidly toward the horse’s eye, looking for the horse to blink).

Let’s now meet Victor, a 32-year-old Quarter Horse gelding with reduced tear production and mild sinking of his globes (eyeballs) due to orbital fat loss associated with old age. Together, these can negatively affect tear film stability on the surface of the eye and potentially contribute to infection. Recently, Victor also scratched his cornea—the surface of the eye—on the corner of his water bucket, resulting in a red, painful, “hot” eye.

Normally, an ulcer like this heals in about 24 to 72 hours with appropriate veterinary intervention. Luckily for Victor, so did his. If ulcers fail to heal swiftly, however, they can progress to superficial nonhealing ulcers, which can be challenging to treat. They typically require surgical intervention, subpalpebral lavage systems, and extended care in a hospital.

Other eye conditions affecting senior horses include corneal disease (e.g., fluid accumulation/edema, opacities, and scarring); glaucoma, which becomes increasingly common with advancing age; cataracts; degeneration of the vitreous (the liquid filling the globe); and ocular masses such as squamous cell carcinoma.

Take-Home Message

We have a strong bond with and care deeply about the older horses that have been with us for decades. “Yet despite this, some owners can reduce care of our seniors, especially after retirement,” says McGowan. “Aged horses require the same, if not higher, level of care as their younger counterparts.”

Most older horses suffer from manageable chronic conditions. Providing the necessary care will improve their quality of life for the duration of their golden years.