Thehorse.com - Full Article
by: Karen Briggs
May 01 2000
Is your horse old enough to vote? Then he's an equine senior citizen by some standards. These days that's not so rare; more and more horses are living into their 20s and 30s, and even beyond. This is a direct result of the improved level of veterinary care we've been able to provide for the last 30 years or so. In particular, the availability of modern deworming medications, such as ivermectin, is widely considered the biggest single contributing factor to our horse's newfound longevity.
Nutrition plays a role as well. Horses which have been correctly fed all their lives are far more likely to live to a ripe old age than those which have been starved or those which have struggled with obesity and its frequent partner, laminitis. That, too, should come as no surprise; the same is true of humans. Diet affects the function of virtually every system in the horse's body -- from the firing of his muscles (fueled by dietary energy sources like carbohydrates and fats) to the formation of new tissues (facilitated by the "building blocks" in protein called amino acids) to the function of his every chemical system (which requires trace minerals such as magnesium, sulfur, and cobalt to help form enzymes, hormones, and other influential "messengers" for the cells).
As your horse ages, however, all of his systems slow down a little. He begins to need more fuel to do the same tasks. His eyesight and hearing might become a little less acute, his legs move a little less swiftly. His gastrointestinal tract can become less efficient at extracting the nutrients he needs from his food. At the same time, his body's ability to thermoregulate (maintain an even body temperature) gradually decreases, so he might need extra dietary energy to help him stay warm in winter, and assist him in coping with heat and humidity in summer.