Twenty percent of the U.S. horse population is now over the age of 20. And with age comes increasing risk for several conditions, including colic, pituitary pars intermedia dysfunction (PPID, aka equine Cushing’s disease), dental disease, and weight loss/gain. Fortunately, nutrition can aid in managing these issues. After all, “age is a number, not a disease,” said Megan Shepherd, DVM, PhD, Dipl. ACVN.
Shepherd, a clinical assistant professor in Virginia-Maryland College of Veterinary Medicine’s Department of Large Animal Clinical Sciences, in Blacksburg, Virginia, talked about feeding considerations for seniors at the 2016 American Association of Equine Practitioners Convention, held Dec. 3-7 in Orlando, Florida.
Calories and Energy
While it’s good practice to assess and address body condition score (BCS) at all life stages, weight management is particularly important for senior horses. Shepherd said a score of 5 out of 9 is ideal for seniors. A horse with no metabolic issues can have a BCS of 6 to account for future weight loss due to illness, she added. An arthritic animal might fare better with a little less weight stressing those joints, in which case a BCS of 4 is acceptable.
Inactive and/or overweight seniors have lower energy needs than hard keepers that have trouble maintaining weight. Hard keepers often benefit from higher fat diets for extra calories, whereas easy keepers or overweight horses generally fare well with forage-based diets plus an added ration balancer.
Water is the most important component of any horse’s diet. Ensuring a senior horse has free access to fresh water can reduce his colic risk. Water requirements increase with forage intake, especially in winter. Consider water temperature and source. In winter, said Shepherd, make sure water is free of ice, and warm it periodically, if possible. Horses with PPID tend to drink and urinate more and, so, have increased water requirements.
Good-quality forage should be the basis of the horse’s diet. If forage alone does not meet a senior’s energy requirements, consider feeding beet pulp, a commercial senior feed, or a fat supplement to increase calorie intake.
Typically, when forage meets a horse’s energy requirements, it also satisfies that animal’s protein requirements. However, Shepherd recommends feeding a ration balancer to horses consuming forage-only diets to be sure they consume enough vitamins and minerals.
If a horse quids, or drops chewed wads of hay, then you might replace long-stem or pasture forage with soaked pelleted or cubed forage. Quidding is tied to dental problems, so don’t forget the importance of caring for your senior’s teeth, Shepherd added.
Other Key Nutrients
Horses with PPID might be insulin-resistant, meaning their cells don’t respond normally to the hormone insulin; therefore, balance these horses’ diets carefully to limit starch and sugar intake.
Vitamin E has strong antioxidant properties. Horse with PPID have decreased antioxidant capacity in the pituitary gland’s pars intermedia, and might benefit from a vitamin E supplement. These horses also might have increased free radical formation, causing increased oxidative damage. Therefore, it could be beneficial to exceed vitamin E requirements for these horses, said Shepherd.
For horses with joint disease, omega-3 fatty acids, particularly marine-based eicosapentaenoic acid and docosahexaenoic acid (you might know these better as EPA and DHA), might help reduce joint inflammation.
Regardless of a horse’s life stage, tailor the diet to his activity level and health need. Remember to offer the basics, such as clean water and good-quality forage, and recruit a qualified equine nutritionist to help guide you when planning the rest of your senior’s diet.