One of the most significant health factors equine practitioners see in their patients is obesity. An overweight body condition has multiple health implications, ranging from metabolic syndrome issues like insulin dysregulation to musculoskeletal crises like laminitis.
Horse owners might not understand the importance of maintaining their horses’ body weight at a good level—a body condition score (BCS) of 5 to 6, where the ribs are covered but there aren’t additional pads of fat over the rump, neck or shoulders. Many horses used for only light recreation are often fed a surplus of energy-dense feed. Too little exercise and too much food has resulted in an obesity epidemic in the equine world.
One solution is to feed less; the other is to exercise more. We advise owners to weigh the food to provide a measured amount and to cut back or even eliminate dietary supplements and pasture. Yet owners of overweight horses are often faced with the sad expressions of “starving” horses that finish their food in 20-30 minutes and beg for more. There is another option available to restrict food intake: slow feeders.
How Does a Slow Feeder Work?
A slow feeder works just as its name describes: It slows feed intake by making it more difficult for a horse to gulp down a large amount of hay at once, instead making the horse work for it by limiting access with holes or netting in the feeder contraption. This gives a horse a chance to eat slowly and over longer periods, satisfying his need to chew and simulating a more natural, trickle-feeder grazing condition that also benefits gastrointestinal health and improves digestion.
A slow feeder keeps hay in front of the horse for longer periods. This also helps minimize the risk of gastric ulcers by generating buffering saliva with chewing and presenting the stomach with small amounts of feed similar to how a horse would forage in pasture. Fiber in the stomach also protects against acid splashing against the sensitive mucosal lining in the upper portions of the stomach.
Another great benefit of a slow feeder is that by confining the hay in one place, you have less wastage and hay isn’t strewn all over the barnyard to be blown away, stepped on, or used as a urinal. And, by placing the feed in a slow feeder with a solid bottom, horses aren’t likely to consume as much dirt and sand trying to pick up pieces off the ground.
An additional bonus: The availability of hay for longer periods helps relieve a horse’s boredom. A herd feeding situation does best when several slow feeders are spaced sufficiently apart. This decreases chances of feed aggression and bullying by dominant horses, as they are preoccupied with obtaining hay from the feeders. In addition, the hay isn’t consumed so rapidly that the dominant herd members eat it all before less dominant horses have a chance.
Types of Slow Feeders
Methods of securing hay in a container that’s still accessible to the horse vary widely.
Haynets can be hung from the rafters, against a wall or in a horse trailer and are common devices for offering hay
to a horse. However, to serve as a slow feeder, a haynet must have an appropriate netting size of 1- to 2-inch openings made from webbing material that is 1-inch wide. Some haynets are large enough to hold an entire bale of hay, but you must take caution to ensure that hooves or horseshoes can’t become entangled. When using a bale-sized feeding net over hay, placing it into a water trough protects limbs from the netting.
Hay bags are made of canvas or heavy-duty material with openings covered by webbing. These come in different styles with various arrangements for food access—front and bottom, front and back or just the front. A slow feeder hay bag is a good choice to use in stalls and for traveling horses.
For safety reasons and easy access, many owners hang haynets and hay bags at head height, but this arrangement
can exacerbate respiratory problems in sensitive horses. At this height, horses are more likely to inhale dust and debris irritants into their airways.
Metal tubs or cylinders with drop-down metal grates should have grate openings no wider than a couple of inches, so they slow hay intake.
Plastic polyurethane tubs with drop-down trays with feeding holes are the safest and most satisfying feeders for horses.
Trough-like feeders of metal or polyurethane grates or trays encourage head-down eating and enable the horse to blow material from his nose as he eats. The tubs and boxes should be cleaned regularly to prevent buildup of dusty hay debris and leftover feed that molds when wet.
Slow feeder webbing or grates work best to slow feed acquisition with spaces of 1.25 to 1.5 inches between holes. This size slows intake without frustrating the horse.
Slow grain feeders have separators or cups within the containers so the horse must work harder to access concentrates. Slower eating of concentrates helps reduce the risk of choke. Also, grain contained within the feeder endures less spillage and wastage. Using a similar strategy, some might elect to put rocks or small balls into a regular rubber feed pan to slow a horse’s concentrate intake.
Grazing muzzles, while not technically slow feeders, do slow a horse’s intake of pasture grass. Most horses tolerate these extremely well, and it allows for turnout and exercise without the horse gorging on too much rich green grass. The “bucket” of the muzzle has a hole at the bottom that can be closed down with Gorilla tape to further limit intake. The bucket’s design allows the horse to drink without problem. Horses seem happy to move around in the pasture with a muzzle on, and they become quite adept at nibbling grass through the bucket hole—yet intake is well-controlled. Factor time on pasture into how much grass a horse is allowed to eat. Some owners use a grazing muzzle to slow hay intake at feeding times rather than providing the horse with an actual slow feeder system.
Slow Feeder Safety Issues
It is tempting to consider cost-saving measures by building your own slow feeder. Take precautions, however, when considering materials that minimize hazards to a horse’s teeth, gums and lower legs. Metal materials, sharp edges or thin cords instead of webbing all pose problems. Wood material splinters and breaks. Regular monitoring and upkeep are important whether a feeder is commercial or home-made, as it takes a lot of punishment over time.
Haynets can be used safely provided you consider certain measures. If hung too low, a horse can get a leg, hoof or horseshoe stuck in the netting. A net with too large a mesh makes it too easy for the horse to grab hay and defeats
the purpose of slowing down eating. Large mesh could also entrap a horse’s head. Too small a mesh poses a hazard to teeth getting stuck and pulling away sensitive gum tissue, especially for a horse plagued with a loose tooth.
A haynet is best suspended with a firm wall or fence behind it, so the horse has leverage to remove the hay. Using attachments in two places further secures the net so it isn’t flailing with each bite. An additional safety measure ties the net with breakable twine or string rather than unbreakable rope or strapping. The lowest part of the net, including when empty, should not drop below a horse’s shoulder.
Metal feeders with grates have their own set of problems, most notably extra wear of incisor teeth and gum injury. A metal grid has the potential to tilt, setting up a hazardous situation. A foot placed in the feeder is also at risk for entrapment and injury from unyielding metal.
Plastic tub feeders seem to offer the greatest safety, particularly those with a tray with holes that drops down as the hay volume recedes. These are usually rounded containers with no abrupt or sharp edges and aren’t likely to entrap a hoof or horseshoe.
If using a grazing muzzle to control intake, use breakaway straps so a horse doesn’t hook it on a protrusion. Take note of where you place slow feeders that are situated outside; the best locations are away from mud and constant moisture that can cause hay spoilage. The objective with any slow-feeding arrangement is to slow a horse’s eating pattern without causing intense frustration. The plastic tub with a drop-down tray seems to provide just the right amount of hay accessible from the holes and has the greatest safety features. The type of hay installed in the feeder must be loose enough for a horse to pull it apart for access. Some hays, like alfalfa, tend to be baled tightly and might need to be fluffed up a bit when added to the feeder.
The Bottom Line
When educating horse owners about the dangers of equine obesity and managing feed intake, there are a number
of options to consider that promote a horse’s mental comfort while staying in step with his digestive evolution. Once a farm is set up with an appropriate slow feeder system, owners can better control weight while keeping their horses satisfied with a longer duration of access to food.