These days, many of our horses are living much longer lives due to horse owners having a greater appreciation and knowledge of the special needs that these older horses require.
In general terms, a senior horse is one who is over 20 years of age. Many senior horses now live well into their late 20s and 30s, with many ponies living into their 40s.
The longevity of these seniors is related to how well that horse can stay fit, healthy and maintain an adequate body condition score. Essentially it comes down to how well we navigate four key factors:
Nutritional requirements
Dental problems
Presence of environmental stress
Health and disease
Many aged horses suffer from difficulties in maintaining weight and an ideal body condition score and this can worsen when temperatures are cold due to older horses having a reduced ability to thermoregulate.
The main causes for a geriatric horse to suffer from weight loss include:
As much as we worry about a horse being underweight, it's also vitally important that we don't allow these senior horses to become overweight as this will put extra stress on their bones, joints, muscles and hooves.
As a rule of thumb, horses require between 1.5 - 2% of their body weight as roughage daily. This requirement will increase in cold weather.
Studies have also shown that nutrient absorption by the digestive tract decreases as the horse ages. The hindgut loses some of its ability to digest fibre, therefore they need to be fed more, to get the same amount of nutritional goodness and combat weight loss.
High-quality soft pasture hay and lucerne are good options. You want to avoid any hay that is too mature or has too much stem - these hays contain more insoluble fibre and are harder for the digestive system to ferment.
Fibres such as sugarbeet pulp or soybean hulls are easily fermentable in the hindgut and make a good source of fibre for these old horses and ponies.
The hindgut in an older horse also doesn't produce B vitamins or biotin like a young horse. It is worthwhile considering supplementation of these in the diet.
And let's not forget that phosphorus absorption in the hindgut declines as the horse ages and as such will require supplementation.
Protein absorption in the small intestine also declines with increasing age, leading to possible muscle wastage and/or cachexia (when the body uses its own muscle protein as a source of fuel).
It's wise to remember that not all protein is created equal. You want to choose a protein that is highly digestible but doesn't produce too much waste product to put extra stress on the liver and kidneys.
Good sources of high-quality protein include:
Digestion of carbohydrate in the small intestine is also altered in the aged horse due to a decline in a carbohydrate digesting enzyme.
To aid digestion of the starch component of grains, the vast majority of senior feeds consist of some form of cooked grains (boiled, extruded, pelleted, micronised or steam flaked).
If your horse has difficulty digesting grains, your vet or equine nutritionist may recommend the addition of starch digesting enzymes.
It's also wise to consider paddock hierarchy or the herd pecking order. As horses age they move down the ladder and at feed time may be bullied by younger members of the herd.
Older horses, especially those with fewer teeth need time to eat so that they are not rushed. Consider feeding these oldies separately, giving them plenty of time to eat and enjoy their food.
Immunity and the ability to fight disease declines with age. Appropriate horse care involving an annual health check and a dental exam ensures that we keep on top of any niggles and identify potential disorders before they become difficult to manage.
The most common geriatric health problems we see include:
Approximately 60% of horses over the age of 15 years suffer some form of periodontal disease and/or tooth loss.
Gum disease is painful and often leads to permanent damage and the requirement for teeth to be removed by an equine dental vet.
Tell-tale signs that your horse may be suffering from tooth disease and require a dental exam include:
Check out our article on dental disease in the aging horse for more detail on how to provide dental care for your horse's teeth.
Equine Cushing's Disease, otherwise known as Pituitary Pars Intermedia Dysfunction (PPID) occurs when there is dysfunction of the pituitary gland and an increase in circulating cortisol in the body.
Clinical signs that your horse may have Cushing’s Disease include:
While there is no cure for PPID, there is medication available that your vet can prescribe that can minimise these symptoms.
Medication, care with diet and regular hoof care will allow your PPID horse or pony to manage absolutely fine.
Our article on Cushing's Disease and Metabolic Syndrome goes into more depth about this disease.
ust like younger horses who are more prone to an increased worm burden, as horses age they too become less immune to parasites and their worm burden often increases.
Faecal egg counts are even more important in this age group to determine an appropriate deworming program.
Take a look at our article on worm drench and selection and use in horses to learn more about parasite control in horses.
Colic is arguably one of the most common medical problems that veterinarians are called to examine geriatric horses for.
The most common type of colic seen in this age group is strangulating small intestinal lesions. It is interesting to note that the success rate for surgery and recovery in this population is equal to younger horses. The key is early referral and surgical intervention.
Many horses and ponies suffer from some degree of painful musculoskeletal problem such as arthritis. To keep them comfortable it is worthwhile discussing nutritional supplements such as green-lipped muscle or medical management with nsaids with your veterinarian.
To improve quality of life it is imperative that we encourage regular exercise and movement, beyond that of just paddock turnout. The saying 'use it or lose it' applies to horses just as much as it does to us.