Fifteen Fascinating Facts About Horse Digestion
I think many of us tend to ‘humanize’ our horses. We think they should be clean. We think they should wear nice, warm blankets when it’s cold. And we think they should eat two or three meals a day–just like we do.
But horses are horses–not humans. And we shouldn’t treat them as such. They like to get dirty. They can regulate their own body temperature in most cases. And they have a unique digestive system that is very different from ours.
If you have horses or are considering getting a horse, I’d say understanding horse digestion should be a top priority. And while it may seem that the horse’s digestive system is quite delicate, you’ll find that many of the common digestive problems that do occur are due to the unnatural manner in which we feed our horses.
Here are fifteen fascinating (and good-to-know) facts about horse digestion:
1. The horse is classified as a non-ruminant herbivore. It’s digestive system resembles a cross between a monogastric animal (such as dog or man) and a ruminant (such as a cow.)
2. As forage (the horse’s natural food) is chewed by the horse, the salivary glands produce up to 10 gallons of saliva (per day). Saliva is crucial for neutralizing stomach acids and reducing the risk of gastric ulcers.
3. The esophagus, which empties into the stomach, only works in one direction for the horse. Food can go down, but cannot come back up (as in regurgitation or vomiting.)
4. The capacity of the horse’s stomach is only about 2 gallons, which is quite small compared to other parts of the digestive system.
5. Food only remains in the horse’s stomach for about 15 minutes before moving on to the small intestine.
6. When the stomach is empty, acid can attack the squamous cells in the stomach lining, often resulting in ulcers. This is why small frequent meals, access to a slow feeder, or access to pasture are important.
7. The majority of the digestion and absorption of sugars, starches, proteins, and fats occurs in the small intestine.
8. Horses don’t have gall bladders. Instead, the duodenum (segment of small intestine that connects to the stomach) aids in the digestion of fats.
9. Food enters and exits the cecum (also known as the ‘blind gut’) at the top. If a horse doesn’t have adequate water intake, this can be a common site for impaction colic.
10. The cecum and other parts of the large intestine contain active populations of bacteria and other microbes which help break food down in a process called fermentation.
11. The bacterial and microbe populations become specific in fermenting the type of food the horse normally eats. When a new food is introduced suddenly, the bacteria/ microbes cannot ferment it effectively and the result is often colic. (This is why all feed changes should be made very gradually.)
12. ‘Gut sounds’ or borborigmus are a sign that food is moving through the digestive tract. An absence of gut sounds likely means there is a blockage (colic.)
13. A horse requires a minimum of 1% of his body weight daily of long-stemmed roughage (grass/ hay or some hay replacers) for normal digestive tract activity. (This would be 10 pounds of roughage for a 1000 lb. horse.)
14. The entire digestion process (from mouth to manure) for the horse takes anywhere from 36-72 hours on average.
15. If it were to be stretched from end to end, the horse’s digestive tract would be about 100 feet in length.