The number of horses aged 16 – 20 years has increased in the United States. Most of these older horses lead healthy and useful lives. However, horse owners may notice that the nutritional needs of their aged horses appear to have changed as it becomes more difficult to maintain adequate body weight. Actually, low body condition is a common problem in geriatric horses and can be caused by bad teeth, kidney or liver disease, or pituitary pars intermedia dysfunction (PPID or equine Cushing’s disease). Disease and reduced feed digestibility are frequent causes of poor body condition in older horses; however, alterations in diet and feeding management may be all that is necessary to correct weight loss in the aged horse.
Reduced feed intake may be influenced by herd social dynamics. The older horse that once was the “boss mare” may have lost her place in the pecking order to another horse and therefore has difficulty accessing feed. Loss of a companion horse may also upset the pecking order and can lead to decreased appetite and feed intake. In these circumstances, feeding the older horse in a separate location away from the rest of herd may vastly improve feed intake, especially in an aged horse that eats slowly because of bad teeth. Conversely, if the older horse is normally fed alone, the addition of a companion horse may improve feed intake.
In addition to problems with adequate feed intake, the older horse may have osteoarthritis, which limits mobility. In this case the horse is hesitant to move around a pasture in search of forage. Housing the horse that is reluctant to move in a flat corral where water, feed, and shelter are in close proximity may improve feed consumption. When osteoarthritis affects the forelimbs or the neck, the horse may experience pain when lowering its head to graze. Providing hay in a raised feeder or hay net may improve the horse’s comfort while eating, which will encourage greater intake. Keep in mind that pulling hay from a hay net may also be difficult for a horse that has arthritis in its neck, so the use of a hay net with large holes would make it easier for the horse to remove hay.
Horses that suffer from dental problems will benefit from regular oral examinations and corrections. When oral health is such that horses have difficulty chewing long-stem hay, modifications to diet can help improve feed intake and subsequent body condition. Horses with mild dental problems can be fed high-quality forages that are soft and have a high leaf-to-stem ratio. Feeding chopped hay is another alternative, especially if the horse is prone to choke. In cases of severe dental problems, horse owners can feed commercial feeds that are specifically formulated to meet the requirements of senior horses. These feeds may need to be soaked in warm water prior to offering them to horses with little to no teeth. Feeds soaked in water increase in volume and may result in reduced feed intake if offered all at once. To encourage adequate intake and reduce the risk of colic or diarrhea, the horse should be fed small amounts of the soaked feed at least four to five times per day.
In summary, senior horses 16 – 20 years or older who are in good health and body condition require little to no dietary modifications. Horses that cannot maintain proper body condition may benefit from diet and management changes. Aged horses that are thin and not suffering from disease may do well with a highly-digestible diet that provides 12 – 16% crude protein. Horses in poor condition that have bad teeth may show improvements in feed intake when long-stem hay is replaced with soaked alfalfa hay cubes or commercial senior feeds.
Jarvis, N.G. 2009. Nutrition of the aged horse. Vet Clin Equine. 25:155-166