Horses are naturally “trickle feeders,” meaning their digestive system is designed to process small amounts of forage almost continuously throughout the day. This biological reality dictates that a domestic feeding schedule must prioritize constant intake to maintain digestive health. The frequency of feeding is as important as the quality and quantity of the feed itself.
The Horse’s Digestive Imperative
The horse’s digestive anatomy is the primary reason why frequent feeding is necessary. The stomach is relatively small, holding only about two to four gallons, meaning it is built for small, continuous intake rather than large, infrequent meals. A large meal can quickly overwhelm the stomach, pushing undigested material into the small intestine, which can lead to digestive upset like colic.
A horse’s stomach continuously produces hydrochloric acid, up to nine gallons per day, regardless of whether food is present. In a natural grazing state, chewing forage produces saliva, which contains bicarbonate that acts as a natural buffer to this acid. When a horse goes for long periods without eating, the acid irritates the stomach lining, particularly the upper, non-glandular region lacking a protective mucus layer. This prolonged exposure to acid is a direct cause of gastric ulcers.
Forage: The Foundation of Frequent Feeding
Forage, including hay and pasture, must be the foundation of the horse’s diet and should be provided with near-continuous access. The goal is to mimic the horse’s natural grazing behavior, which can occupy them for 12 to 18 hours a day. A horse should ideally not go longer than four to six hours without some form of forage.
Allowing the stomach to remain empty for longer than this four-hour window significantly increases the risk of gastric ulcers and other digestive issues. To achieve near-continuous intake, especially for stabled horses, owners can employ practical methods. Using slow-feed hay nets or bags is an effective strategy, as the small openings force the horse to eat more slowly, extending the duration of the meal.
Multiple feeding stations can also encourage movement and mimic the natural foraging process. Even for horses on a restricted diet for weight management, the total daily forage ration should be divided into as many small portions as possible. This division prevents long stretches of an empty stomach. Soaking hay can also be used to reduce sugar content for certain horses while still providing necessary fiber and chewing time.
Concentrates: Scheduling Grain and Supplements
Concentrates, including grains, pellets, and commercial feeds, must be fed in small, frequent meals to ensure safety and proper digestion. The small intestine is the primary site for digesting the starches and sugars found in these feeds. If a horse consumes a large amount in a single meal, the small intestine can become overwhelmed and unable to process all the non-structural carbohydrates (NSC).
Undigested starch then passes into the hindgut (cecum and large colon), where it ferments rapidly. This process causes a drop in the hindgut’s pH, leading to hindgut acidosis. Acidosis can kill beneficial microbes and significantly increase the risk of severe conditions like colic and laminitis. A general guideline for an average 1,100-pound horse is to feed no more than 0.5% of their body weight in high starch/sugar concentrates per meal, which translates to approximately five pounds.
For horses requiring a higher total daily amount of concentrate, the ration must be divided into two or three meals per day, or more for high-performance animals. Feeding hay or other forage before the concentrate meal can help by slowing the rate of intake and providing a fiber mat in the stomach. This approach ensures the digestive system can efficiently process the nutrients without overloading the hindgut with starch.
Adjusting the Schedule for Individual Needs
The standard feeding frequency must be modified based on the horse’s specific circumstances, including workload, age, and health status. High-performance horses, such as racehorses or those in intense training, have higher energy demands requiring more frequent concentrate meals. Dividing the concentrate into three or four smaller meals throughout the day, rather than two large ones, helps meet caloric needs while staying within the safe starch limit per meal.
Senior horses, particularly those with dental issues, often require a different frequency for their modified diets. Because they struggle to chew long-stem hay, their forage is often replaced with soaked hay cubes, pellets, or mashes. These alternative fiber sources should be fed in multiple small meals, ideally four to six times per day, to ensure adequate fiber and calories without overwhelming their system.
Horses with metabolic conditions, such as Equine Metabolic Syndrome (EMS) or Insulin Dysregulation, require careful timing to manage blood sugar levels. While they still need frequent forage access, their hay must be tested for low non-structural carbohydrate content (ideally less than 10%). Their concentrate intake is often replaced with a low-calorie ration balancer. Horses on stall rest or limited turnout benefit from more frequent, smaller hay portions to keep them occupied and prevent long periods of digestive inactivity.