At what age do horses become “geriatric?” Dr Anthony Blikslager from North Carolina State University suggested that horses over the age of 20 might reasonably be considered as geriatric, while speaking at the British Equine Veterinary Association’s annual congress recently.
This represents an animal that has lived for three-quarters of its expected lifespan, assuming an average equine life expectancy of approximately 27 years. In human terms, a 20-year-old horse is equivalent to a 60-year-old person.
There is considerable evidence that geriatric horses are more likely to suffer from colic than younger horses. Recent work has also shown that colic is the single most common disease for which medical attention is sought in the older horse. This is likely to be due to a lower prevalence of orthopaedic and athletic injuries in geriatric horses as well as an increased prevalence of colic.
Dr Blikslager highlighted some of the different types of colic that are diagnosed most commonly in geriatric horses. Impactions due to poor teeth are common in older animals as their teeth succumb to the wear and tear of a grass-based diet. Grass may look soft and juicy but it contains high levels of silicates — sand-like particles — that are among the hardest compounds in nature.
Regular dental inspections and corrective treatment by a vet or equine dental technician can ensure that the teeth of a geriatric horse remain functional for as long as possible.
Another type of colic that is associated with older horses is strangulation of the intestine by a pedunculated lipoma. This is a fatty lump that grows on a stalk in the horse’s abdomen and, in some horses, will wrap tightly around a loop of intestine preventing the blood supply from reaching the gut. When this happens the gut dies within a matter of hours.
Horses suffering from this particular type of colic must have the affected intestine removed surgically, and the sooner it is removed the better the horse’s chance of making a full recovery.
Dr Blikslager’s research, and that conducted at Leahurst, University of Liverpool, indicates that older pony geldings are at particular risk from this type of colic. It was suggested that preventing animals becoming excessively fat may decrease the rate of lipoma growth.