Horses that are missing incisors might have a hard time grasping short plants in overgrazed or mowed pastures.
Photo: Anne M. Eberhardt/The Horse
If your horse has few to no teeth, he might not be chewing and digesting the nutrients he needs to maintain his health
Choppers. Ivories. Pearly whites. Tusks. We have an array of words to describe our all-important teeth. Their most important characteristic? The ability to bite and chew food so we can digest our meals (and, hence, absorb nutrients) properly. In horses, the loss of one or more teeth can severely impact the ability to forage and masticate (chew). If you have such a dentally impaired horse—or you own an older equid whose days with a full mouth of teeth are numbered—read on as we dive into the unique topic of feeding the (nearly) chopperless horse.
To understand how to feed a toothless horse, it’s important to know what exactly teeth do. Let’s start by reviewing some basic dental anatomy: In the front of the mouth, just inside the horse’s lips, are the incisors. These are the first teeth that develop after just a couple of days of life. By age 4 ½, six upper and six lower permanent incisors will have replaced the “baby” incisors. Further back in the mouth reside the cheek teeth, or premolars and molars. Foals develop 12 premolars within a few weeks of age. Permanent premolars replace these by 4 ½ years, along with 12 molars just behind them. Wolf teeth typically erupt when the horse is 1 to 1 ½ years old. These two short teeth sit directly in front of the premolars on the upper jaw, and most owners have them removed. Male horses also have two pairs of canine teeth situated behind the incisors.
Why Teeth Might Be Missing
Horses, just like humans, only have one set of permanent teeth to maintain for their entire life. Therefore, keeping that set full is ideal. Jack Easley, DVM, MS, Dipl. ABVP, a private practitioner with a focus on dental care based in Shelbyville, Kentucky, describes why permanent teeth might be missing. The most common cause is periodontal disease in older horses, but Easley says other, rarer situations do arise.
“Expanding masses, such as cysts or tumors in the horse’s head requiring removal, may also require the removal of dental buds,” he says. Without dental buds, a tooth will not form. Cracked or infected teeth are candidates for removal to prevent secondary issues, such as sinus infections.
Because horses have hypsodont (tall and erupting continuously from the gum) teeth, they are at risk of simply running out of tooth. The chewing process constantly wears away at permanent teeth. As this happens, more of the tooth that is hidden in the gums becomes exposed. Horses have about 4 inches of tooth to work with, but the older they get, the more likely it is that they’ll either lose their teeth completely, or any remaining teeth will be too smooth for useful chewing.
It’s easy to connect the dots to see that a large majority of the toothless equine population is, in fact, geriatric. Several surveys done on the aging horse population in Europe in 2011 found that about 96% of senior horse owners reported dental abnormalities in their animals. A few years prior, in 2008, researchers studying the relationship between age and digestion had theorized that there might be a minimum amount of tooth needed for proper chewing, although they have yet to quantify that figure.
Regardless of the type or number of teeth your horse is missing, it’s important to understand how it will compromise his ability to chew and digest feed. We know that for all horses, forage provides the essential fiber necessary for proper digestive function and health. But several factors might make traditional forage—hay and pasture—a less-than-ideal option for toothless horses.
“Horses missing incisors might have difficulty grazing short plants, so if they are in a paddock that is overgrazed or mowed to a short height, it could be hard for them to grasp and nip the plants off,” explains Laurie Lawrence, PhD, professor of equine nutrition at the University of Kentucky, in Lexington. Although turnout is still important, do not rely on pasture to be a major source of nutrients for incisorless horses.
Horses without molars have difficulty grinding their feed, Lawrence says, so avoid feeds that require this process, whether it’s to break hard seed coats (in corn, wheat, or sorghum) or to reduce particle size prior to swallowing (such as with long stem grass or hay). This is particularly important because wads of hay or grass called boluses can lodge in the esophagus, causing choke. “If the molars are missing, then the feed must be preprocessed to some extent,” she says.
Knowing all of this, building a total ration for a toothless horse based on forage might be quite a feat. Adding age into the equation, as some evidence suggests that aging might compromise nutrient digestion, particularly of fiber and protein, only complicates things. Luckily, these equids still have plenty of feed options. As far as forage goes, toothless horses should always have free-choice access to either pasture or hay, allowing for a more natural foraging behavior to help decrease the chances of digestive upsets, such as gastric ulcers and colic, developing. Choke-prone horses are the only exception to the rule and should not be allowed access to long-stemmed hay or pasture. That’s when alternative fiber sources come into play; hay cubes, pellets, chopped forage (or chaff), and beet pulp can provide quality fiber to the diet of horses no longer able to chew long-stemmed forage.
To help your horse get the most nutrients out of grains, such as oats and soybeans, choose a product that’s been processed by pelleting or extruding. Rutgers University researchers have found that feeding a pellet/extruded mixed ration improves body weight, health, and coat condition in aged horses better than traditional sweet feeds. In the pelleting process feedstuffs are ground, mixed together, pressed through a die, and cut to a desired length. Steam, used to gelatinize starch, can further increase digestibility.
Pelleted feeds offer several advantages: They allow for a more uniform distribution of ingredients, prevent horses from sorting grains, and usually contain higher fiber components such as beet pulp. But keep in mind that horses often consume pelleted rations more quickly than other feeds, as supported by research done in pony mares in the United Kingdom. Lawrence suggests that feeding forage before the concentrate might slow down intake.
During the extrusion process grains are ground, mixed together, exposed to high steam and pressure, and forced through a die, where they expand and form a kibble shape prior to cooling. Extruded feeds can improve horses’ starch and protein digestion and might extend eating time.
Complete feeds are those formulated to meet all of a horse’s nutritional requirements without hay or pasture. These all-in-one products are typically pelleted rations high in crude fiber (>16%) that contain a variety of digestible fiber sources such as alfalfa meal, soybean hulls, and beet pulp. Generally speaking, you can offer complete feeds with or without hay or pasture. When fed without forage, feeding rates should be at least 1% of body weight per day to meet the horse’s daily fiber requirements. Not all high-fiber, pelleted feeds are considered complete feeds, but one quick check of the label’s feeding directions will tell you whether the product should be fed with forage. The chart below can help you gauge your horses’ complete feed needs.
Owners can easily add a few steps to their daily feeding practices that will positively affect the dentally challenged horse’s digestion and overall health. Dividing feed, especially complete rations, into smaller, more frequent meals throughout the day, for instance, offers several health advantages. This also applies to both concentrates and hay or forage alternatives.
“If you pulverize or soften feed for a toothless horse, the reduced amount of chewing may result in very short meal times,” Lawrence adds. Without adequate chew time, horses might be at risk of developing digestive disturbances, such as ulcers, or behavioral vices. One vice that researchers have tied to lack of quality foraging time is cribbing. Although it might be a challenge scheduling-wise, most nutritionists recommend feeding at least three or four meals (spaced) evenly throughout the day.
Another feeding tip is to moisten pellets, kibble, and hay cubes prior to mealtime. “Chewing results in saliva production, and saliva moistens the feed so it is easier to swallow,” says Lawrence. Therefore, if a horse with few teeth tends to bolt his feed without much chewing, then moistening the feed can help prevent choke. Moistening with water is easy and convenient for most owners, and soaking time is minimal, especially if the water is warm. A good rule of thumb is to add 1 quart of water for every 3 quarts of cubes, pellets, or kibbles. Oil, molasses, and even applesauce are other options for wetting feed, but feeds might require more soaking time in these than in water. A word of caution: Store soaked feed in a cool, dry location—especially during hot and humid weather—to ensure it does not mold. Also, cover it up so bugs or rodents don’t fall in.
For toothless horses, especially those with periodontal disease, dental care and nutritional management is a daily task. Easley says the level of care needed depends on the individual horse, but toothless horses typically require more frequent or in-depth oral examinations to determine the presence of disease than those with a full set of teeth.
In most cases, though, even horses with missing incisors fare quite well, nutritionally speaking. If your horse is having trouble masticating, is quidding forage, or is dropping feed, he might be showing signs of a problem that needs to be addressed, Easley says. However, he cautions that just because an older horse loses weight does not always mean his teeth are the issue. Make sure you schedule a full veterinary checkup, including bloodwork, to rule out any other underlying medical problems.