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Understanding Your Horse’s Digestive System
Understanding horse digestion system.

Does it Seem That Horses Were Designed to Experience Colic
Learn Why Your Horse May Develop Digestion Difficulties?
Article by Reba Martinez for horsesensesolutions.com

Did you ever wonder why your horse’s digestive system seems so fragile?
Did you know horses endured a major environmental change from rain forest to dry grassland and adapted to avoid extinction.

Understand how the digestion works from eating and chewing all the way through and out! Learn along the way what may contribute to impactions.
Did you know that your horse may have digestive problems by becoming dehydrated by simple acts of weather change from warm to cold, change in their routine or an abrupt change in the feed source.  These problems may account for impactions, and the first sign is simply refusing feed or not eating up.

Why is the horse's digestive tract so fragile?   There is actually a really good explanation that scientists have researched; after analyzing fossil data alongside of records of North American climate changes.  The researchers found that the animals diets shifted from rain-forest fruits and leafy vegetables to the more abrasive diets found in grasslands.  
When horses first came into being, they were located in a rain forest type environment of vegetables, fruits and lush leafy greens.  This would be like you eating a large veggie salad.  As time passed on, the land went through a climate change from being a rain forest to a dry climate where the same vegetation would not grow.  Only a dry grass land came into existence.  The horses were faced with becoming extinct if they did not adapt to the environment.  Can you imagine if you changed today from eating a nice supple leafy veggie salad, to eating grass on your lawn or even dry hay?  Your body and the horses were not designed to break down those fiber roughages for food source.  In nature the horses adapted to their environment which was a successful survival strategy.
Horses grazing.

The ancient ancestors of Equidae (The horse family) developed the ability to digest the dry climate vegetation grasses.  Eating grass, which is a difficult to digest, was a successful survival strategy.  During this period many species were unable to adapt to eating grasses and became extinct . However this survival strategy came with a price. Horses are non-ruminant herbivores of a type known as a hind-gut fermenter. This means that horses have a simple stomach, just like us.  However, unlike humans, they also have the ability to digest plant fiber (largely cellulose) that comes from grass and hay.

They differ from ruminants (cattle, sheep and deer), which digest fiber in plant matter by use of bacteria in complex multi-chambered stomach to digest fiber by fermentation and use enzymatic digestion in the small intestines; a far more efficient digestive system.
Horses developed, because of means of survival, a delicate but unique dual system.  The foregut is where digestion of simple carbohydrate sources such as starch from grain occurs.   In the hindgut is where the fibrous sources such as oat hulls, beet pulp and hay occur.

Foregut consists of: esophagus, stomach, small intestine and cecum.  Hindgut consists of: cecum and colon.
Digestion is by microbial enzymatic fermentation and takes place in the fore gut ahead of the cecum; the crude protein digestion and virtually all soluble carbohydrate digestion.  At this time the fiber is not broken down and moves on through the digestive tract. Where broken down later by the fermentation vat called the Cecum and then absorbed in the colon.     
The horses have adapted to breaking down fibers, but they are not a ruminant type animal like the cow. They are classified as non-ruminant.   That is why they need to be watched carefully to avoid deadly complications.
Understanding our horse's digestive system.

To have a better understanding of horse's digestion, I have simplified each phase of the digestive system.  This will give you a better understanding how each section works.

Mouth:   Feeds are mixed with saliva in the mouth to make a moist bolus that can be easily swallowed. Three pairs of glands produce saliva. Horses will produce up to 10 gallons (85 lb.) of saliva per day.  No wonder horses need water at all times to keep hydrated.  Depending on the weather, horses will drink from 10 to 20 gallons of water a day.  Drinking adequate amounts of water will lessen the risk of having impaction colic.  Check waters daily.  I think dehydration is the number one cause of impaction colic.

Teeth: Horses need to chew their feed for better digestion to occur.   By breaking down the feed stuffs, it allows the enzymatic and microbial action to penetrate the plant cell walls and digest feed more efficiently. The horse needs healthy teeth to grind feed. Teeth should be examined during the annual health check to ensure that they are wearing normally. The horse’s upper jaw is wider than the lower jaw, so sharp points often develop on the molar teeth. If your horse is dropping feed out of their mouths,  this may be an indication that points have formed on the teeth and they are cutting the inside of their mouth as they chew.  These points may prevent normal chewing which reduces the food value received from the feed and may predispose a horse to colic.  Filing (or floating) the teeth will remove the points. 

Esophagus: The esophagus is a simple muscular tube that takes food from the mouth to the stomach and is about 4-5 feet in length.  A muscular ring, called the cardiac sphincter, connects the stomach to the esophagus.  Because of the angle that it attaches to the stomach and the fact that this muscle is very strong this explains why it's almost impossible for a horse to vomit.

Stomach: The stomach of the horse is small in relation to the horses’ large body. This limits the amount of feed a horse can take in at one time. The natural feeding habit of the horse is to graze on small amounts of roughages often. The average sized horse (800 to 1200 lbs.) has a stomach with a capacity of only four gallons.  In the stomach breakdown of feed stuffs are accomplished by bacteria that produce lactic acid, other acids and the enzyme pepsin.   The end product is food broken down into chyme (The term used to refer to partially digested food as it moves through the digestive tract).

For full digestion to take place, feed may stay in the stomach for up to 24 hours before it moves on. The stomach works best when it contains 2 gallons of feed for full digestion to occur.  The fact is that the stomach empties when it becomes 2/3 full, whether stomach enzymes have completed their processing of the food or not.  Because of the way a horses’ digestive system is designed, it runs more efficiently to feed horses small meals often.  However, horses are now housed in stalls or pens which do not allow grasses to grow.  Horse owners ration the feed.  Horses are now expected to eat large amounts of concentrate once or twice a day.   If you feed a large amount of concentrated grains and hay at one time and the stomach becomes more than 2/3 full it may only stay in the stomach for as little as 15 minutes before it is passed on.  This means the feed stuffs are not fully digested and may predispose your horse to impaction colic.  To avoid this potential problem continuous foraging or several small feedings per day are preferable to one or two large ones. The rate of passage of food through the stomach is highly variable, depending on how the horse is fed. It then leaves the stomach through the pyloric valve, which controls the flow of food out of stomach and into the small intestine.

Small Intestine (Upper Gut): The horse’s small intestine is 50 to 70 feet long and holds 10 to 12 gallons. This is the major digestive organ. After the food has been digested, it is absorbed through the walls of the small intestine and carried off by the blood stream to whatever cells need the nutrients. Nearly 70% of carbohydrate digestion and absorption and almost all amino acid absorption occur in the small intestine. It can take as little as 30 to 60 minutes for food to pass through the small intestine.  Most food is digested and absorbed into the bloodstream from the small intestine, including proteins, simple carbohydrate, fats, and vitamins A, D, and E. Any remaining liquids and roughage move into the large intestine.
The small intestine contains three sections; the duodenum, jejunum and ileum.

Duodenum:   The majority of digestion occurs in the duodenum as bile from the liver aids in digesting.  Horses do not have a gall bladder, so bile flows constantly.

Jejunum:    The Jejunum is important in re-absorption process of bile salts and absorption of nutrients during digestion and is the part of the small intestine where the majority of nutrient absorption occurs. 

Ilium:   This part of the upper gut is primarily a transition area between large and small intestines.
Cecum: The cecum is the first section of the large intestine; a pouch, about 4 feet long that holds 7 to 8 gallons of digestive chyme.  It is a microbial fermentation vat, similar to the rumen in a cow. These microbes produce specialized enzymes which ferment and break down the cellulosic structures of fibrous feeds like hay or any material that was not digested in the small intestine. These bacteria feed upon the chyme, which will remain in the cecum for about seven hours, allowing bacteria time to start breaking it down. The microbes will produce vitamin K, B -complex vitamins, proteins, and fatty acids. The vitamins and fatty acids will be absorbed.  

A potential problem is because of the unique design of the cecum. Its entrance and exit are both at the top of the organ. This means that the feed enters at the top, mixes throughout, and is then expelled up at the top. This design is the cause of problems if an animal eats a lot of dry feeds without adequate water or if a rapid change of diet occurs.  The reason horses must have their diets changed slowly is that the microbial population in a cecum is somewhat specific as to what feedstuffs it can digest. The bacteria in the cecum are slow to modify and adapt to the different chemical structure of new feeds. Too abrupt a change in diet can cause colic, as the new food is not properly digested. Both of these reasons may cause an impaction in the lower end of the cecum.

A good formula to follow with is a concentrated grain based feed or new type hay:
Avoid Sudden Feed Changes: If a change of feed occurs, it takes about three weeks to develop a microbial population that can digest a new feed and maintain a normal flow through the cecum. A general rule for safely changing feeds:
Week 1: Feed a mix of three-fourths of the old ration and one-fourth of the new feed.
Week 2: Feed a mix of one-half of the old ration and one-half of the new feed.
Week 3: Feed a mix of one-fourth of the old ration and three-fourths of the new feed.
Week 4: Feed all new feed.

Colon: The large colon, small colon, and rectum make up the remainder of the large intestine. Microbial digestion continues, and most of the nutrients made through microbial digestion are absorbed here. Water is also absorbed, resulting into the formation of fecal balls. These fecal balls, which are the undigested roughage and mostly indigestible portion of what was fed, are then passed from the rectum.
Large Colon: The large colon is 10-12 feet long and holds up to 20 gallons of semi-liquid matter. It is made up of the right lower (ventral) colon, the left lower (ventral) colon, the left upper (dorsal) colon, the right upper (dorsal) colon, and the transverse colon, in that order. The main purpose of the large colon is to absorb carbohydrates, which were broken down from cellulose in the cecum. Due to its many twists and turns, it is a common place for a type of horse colic called an impaction.

Three tight bends in the large colon arise where these segments meet each other, and these are termed the sterna, diaphragmatic and pelvic flexures. 

Small Colon: The small colon is 10-12 feet in length and holds only 5 gallons of material. It is the area where the majority of water in the horse's diet is absorbed, and is the place where fecal balls are formed.
Rectum: The rectum is about one foot long, and acts as a holding chamber for waste matter, which is then expelled from the body via the anus.

Don’t tell me your horse has never had a digestive problem, just as I am sure you yourself have never had a digestion problem, also?
Some horses tolerate pain better than others and just seem very somber. I hope this article has been an awakening for you –

It's not IF my horse will get colic – It's WHEN   (will it always be your friends horse)
What you should know about impaction colic:   As you followed along the digestive tract, I have brought your attention to reasons a horse may have colic.  It may be your horse’s teeth not properly maintained, over feeding at one time or sudden change of feed, or not adequate intake of water.  Not drinking enough water can be simply as a severe weather change.  Horses drink when weather is warm, but if it suddenly drops overnight to 20 to 30 degrees or lower; the horse does not feel thirsty or hot the next day, so they do not drink adequate amounts.

Colic is the number one killer of horses.  Feed stuffs must be adequately broken down through digestion and flowing properly through a well hydrated horse.  If not, the results are large masses of the chyme being moved slowly and actually trapped in the colon.  Remember as explained above, the colon keeps doing its job as usual, pulling out the moisture to make fecal balls.  When movement of digestion is slowed down, the colon actually pulls so much water out of the feed stuff, that it is now sticking (adhering) to the mucosal lining.

If given mineral oil as a treatment for impaction colic, it will usually not work because the barrier made in chyme sticking to the mucosal lining.  The oil is not getting through to the other end and you do not see it being eliminated.  Also, giving muscle relaxants (NSAIDs) as a treatment for impaction colic will not work because you need the smooth muscles to help with peristalsis (wave like movements) in moving partial digested feed stuffs through. 

SayWhoa!  to horses in distress.  This product assists in reversing the situation to aid in bringing body fluids back into the colon which supples up the mucosal lining which releases the adhering feed stuffs.  Then the ionic solution of calcium plus other natural ingredients aid in promoting smooth muscles needed for peristalsis which assists in elimination of retained stools. SayWhoa!  has been on the market for some time now and is sold in over 700 stores across the United States.  It is also available in Canada.  Why wouldn’t you keep this on hand with a 5 year shelf life, no temperature control and the horse just swallows it with an included oral dosing syringe (even your care taker can give). Use as your first defense when you see signs of colic strike. For more information, go to HorseSenseSolutions.com or call 800-448-8180. 

See why veterinarians recommend this and leading trainers won’t be without it. 
“My first line of defense for uncomplicated colic is SayWhoa.”   
R.S, DVM   Texas
“SayWhoa is working well.  The clients are very happy with the product.”  
B.G, DVM   North Carolina
“Fast acting, horses returned to normal flow of the digestive system.  SayWhoa worked great in uncomplicated cases.”   
B.M,  DVM   Oklahoma

 Monty Roberts Flags Are Up Farms
 SayWhoa! is on hand at Monty Roberts’ Flag Is Up Farms –
Well known as the “Horse Whisperer.”

In our experience here at Monty Robert's Flag Is Up Farms we had 100% success with using SayWhoa!. We had several wild mustangs that we adopted from the BLM and three of them colic in the span of two weeks. We used your product and saved all three including one that was severe and thought to not survive. I highly recommend this product and would always keep a few bottles around for safeties sake.
Kind regards,
Laurel Roberts (Monty Roberts’ Daughter)

Learn more at HorseSenseSolutions.com or call to order 800-448-8180

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