Disease Prevalence in Older Horses Examined

More and more horses are living to a ripe old age, making gerontology a growing part of equine medicine. However, with age comes not only experience but also certain diseases and conditions, according to the results of a recent study.

"Older horses are at risk for a number of health problems such as pituitary pars intermedia dysfunction (equine Cushing's disease), chronic laminitis, recurrent airway obstruction, cancer, and heart problems," noted Joanne Ireland, BVMS, MRCVS, a research assistant at the University of Liverpool in England, whose recent research, funded by the Horse Trust, focused on disease in the aging horse population.

Although geriatric horses (those 15 years and older) comprise almost 30% of the equine population, there is surprisingly little information describing exactly how many geriatric horses have a clinical--and possibly treatable--disease. As a result, many horse owners might not recognize that their horse could have a health problem and instead could mistakenly attribute disease to the "aging process."

To determine how many aging horses are affected by clinical ailments, Ireland and colleagues randomly chose 200 geriatric horses residing in England and north Wales from a survey of owners of 1,144 geriatric horses in this area. All 200 horses were examined by a veterinarian to identify any physical abnormalities.

Key findings were:

  • Twenty-six percent of horses were overweight, but only 4.5% were underweight;
  • Skin conditions were identified in 71% of horses, including hair coat abnormalities, sarcoids (a type of skin tumor), melanomas, aural plaques (white, flaky patches inside the ears), insect bite hypersensitivity, and the bacterial infection dermatophilosis;
  • Almost 25% of horses had hirsutism, or extensive hair growth;
  • Ocular (eye) abnormalities were common, including cataracts in 58.5% of horses;
  • Twenty percent of horses had heart murmurs;
  • Nasal discharge was found in 22% of horses, and clinical signs suggestive of lower airway disease were identified in 13.6%;
  • More than 50% of horses were lame at the trot;
  • Hoof abnormalities were found in 80% of horses; and
  • Dental abnormalities were found in 95.4% of the animals.

"This study clearly demonstrates that older horses frequently have one, and in many cases more than one, health problem," concluded Ireland. "Knowing exactly which diseases are common in older animals will help equine practitioners educate clients about what to look for in their aging horses to ensure they are being properly cared for as they age."

Armed with this knowledge, owners can be vigilant for these conditions and remedy the ones that can be treated with the assistance of their veterinarian. Insect bite hypersensitivity, nasal discharge, and dental abnormalities, for example, are all generally treatable conditions, and the absence of certain ailments could lead to longer and healthier lives for equine seniors.

The study, "Disease prevalence in geriatric horses in the United Kingdom: Veterinary clinical assessment in 200 cases," is scheduled to be published in an upcoming edition of the Equine Veterinary Journal. The abstract is available online.

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.