When we think of horse farms in central Virginia, it’s probably easy to imagine an endless green sprawl with rolling hills, clear blue skies, and horses galloping unrestrained against the rugged landscape. We’re probably less likely to think of horses sitting around in stalls with nothing to do. But horse farmers know the reality; horses, like people are susceptible to obesity given certain conditions. Certain breeds of livestock are considered “easy keepers,” because in conditions that cause most of the herd to lose weight, they are adept at maintaining or even gaining weight. So most of the time it’s better and more desirable than a “hard keeper.” Ponies, as well as most mules and donkeys fit this description, as do many of the smaller, more durable species of horse like the Mustang and the Arabian. Easy keepers are desirable because it’s easy to keep them well-fed, but maintaining nutritional and dietary needs can be difficult.
Reasons for obesity
The forage that we cultivate on our modern-day pastures is much higher in caloric content than what horses were raised on, from an evolutionary perspective. Imagine; the formative horses and their ancestors were raised on forage that was much less nourishing, both nutritionally and calorically. Not only that but the terrain was very sparsely vegetated. The result was a lean, resourceful animal who had to walk several miles just to find sufficient sustenance. Skip ahead to modern times, and we are by and large providing these animals with high-quality forages that are easily accessible, removing their incentive to walk around for miles. All grazing activity is kept within the confines of pasture fencing. So we have food that is nutritionally more nourishing than what horses are used to, combined with a decrease in energy expenditures. It’s the same for humans, especially over the last hundred or so years: we’ve seen the effect of increasingly sedentary lifestyles combined with widespread availability of food. Additionally, there have been advances in agricultural technology over the last century that have seen the phasing out of livestock bred for crop cultivation. The tractor has replaced the workhorse, and most horses now are kept for recreational purposes. This is especially the case on central Virginia horse farms; horses are used for leisure and recreation–activities like foxhunting or exploring trails on horseback.
What happens when horses become obese
It can be difficult to say when a horse is just a bit plump and when it’s actually obese. Not everyone has a livestock scale (although you can pick one up for well under a thousand bucks). Sometimes it’s hard to get a handle on whether or not your four-legged friend may simply be suffering from “big-bonedness.” And of course some body fat is needed. But when your horse actually does reach that point, it should be a cause for concern.
Excess fat detracts from a horse’s ability to exercise. It requires more energy to even move, and so they do it less. More seriously, excess layers of fat can insulate the body. During the summer, this could lead to heat stress because the fat detracts from a horse’s ability to dissipate heat. These extra fat layers can also result in the formation of lipomas, benign tumors that tend to grow in a horse’s abdominal cavity. Lipomas often form on the mesentery, a thin strand of suspended tissue that encloses the intestine. As the tumor develops, it starts to hang from the mesentery, forming what’s called a pedicle. This can prevent ingested material from passing while cutting off blood supply. Obese horses are also more prone to developing laminitis, a hoofed animal disease that can lead to inflammation, hoof sinking, foot tenderness, and inability to walk. This is most likely a result of irregular glucose metabolism.
Treating obesity
Not everyone has access to a livestock scale, but there are otherways to keep track of horse obesity. Weight tapes are pretty good at approximating the body weight of your horse. They’re also useful for tracking weight gains or losses over time. The Henneke horse body condition scoring system was created to develop a standardized scale with which to assess a horse’s body conditions. It assesses weight accumulation across six areas on a horse’s body: neck, withers, behind the shoulder, over the ribs, topline, and tailhead. It gives each of the areas a rating from 1-9: one is extremely emaciated and 9 is obese. Ideal scores are 4-6: you can’t necessarily see the rib but you should always feel it.
Diet and exercise are the two ways to address obesity in any species. In order to address obesity, you must build your horse up to the point where it’s expending more energy than it’s taking in (through calories). This has to be done gradually though; the stress of a sudden surge of physical activity is no good. Say you tend to keep your horses in stalls. Simply letting a pampered horse out won’t really do too much; often, the horses will just stand around waiting to eat. Forced exercise may be necessary at first. Get them to walk around in twenty minute jaunts several times a day, or ten minute runs. Riding the horse is more effective. Consider loaning the horse to someone you know who will want to ride it around. Walking for a long while is considered more effective than galloping for a short while. It’s a steady process; consistency is key.
Next you must think about reducing the amount of grazing your horse does every day. Taper off access to pastures, definitely less than four hours a day. Despite this advice, it’s important to keep the horses eating consistently. Horses that are let out once or twice a day, eat more than horses that are grazing sparsely throughout the day. It’s important to keep the metabolism working. To reduce access to pasture, turn horses out into a drylots (no forage). If you don’t have one on the property, consider a muzzle that lets horses hydrate and consume salt without being able to eat grass. Don’t feed your horses as many high-calorie concentrates, especially if you have an easy keeper. It would also be wise to stick to grass forage and hay instead of legumes like alfalfa. This way, the horses are taking in less calories. Conserve the amount of hay your horses consume. 1.5% of the horse’s target weight is ideal…not 1.5% of its current weight. Try your best to distribute this intake evenly throughout the day instead of in concentrated bursts of eating.
Always consult with your veterinarian before making any abrupt changes to your horse’s diet and lifestyle.
