The Equine Cecum
By Eleanor Blazer
Now you cecum, now you don't.

        When ancient Greeks were studying the human digestive system they discovered a small section of intestine (the appendix) which was a dead-end.  They named it the caecum, which means "blind". 

        Not agreeing with the Greeks, our modern medical community named the small pouch which connects the small intestine to the large intestine the cecum. The human appendix (the Greek's caecum) dangles off the cecum.

       Highly evolved monogastric (one stomach) organisms have a cecum; the functional intensity of which is dictated by diet.  Monogastric creatures that live exclusively on forage-such as your horse--have a very active cecum. 

       Keeping the equine cecum healthy and happy should be one of your horse care goals.  An unhappy cecum leads to a sick horse.
       The equine cecum is a fermentation vat.  Within the cecum are microbes (bacteria and protozoa) that aid in the digestion of cellulose and fiber (structural carbohydrates).  The main source of cellulose and fiber is forage.

       The microbes are somewhat specific as to what they digest.  A drastic change in diet or the arrival of non-structural carbohydrates disrupts the balance of bacteria and protozoa. Excessive fermentation occurs - producing lactic acid, resulting in cecal acidosis. This acidic environment kills large numbers of beneficial bacteria.  The unhealthy environment can lead to colic.  Poisonous toxins are also released into the bloodstream causing laminitis.

        And you don't want any of those things to occur.

        So how do we keep the equine cecum happy?

• All changes in feed must be made gradually. 

        A sudden change of feed disrupts the microbial balance in the cecum.  The bacteria and protozoa must be given time to adjust. 

       When introducing a new feed, start by adding a small amount of the new feed with the current feed.  Over a period of time increase the new while decreasing the old.  It takes about three weeks for the microbial population to be totally adjusted to the new feed and digesting at maximum potential.  Always make feed changes slowly and over a period of at least 14 days.

       This includes forage, grain or commercial products. 

       Many horse caretakers are aware of making the switch slowly when changing grain or concentrates, but the same thing must be done when introducing new hay.  Whether it is a new load of hay from a supplier, from a different field or new hay for the season, it should be mixed with the hay the horse has been eating.

       Plan ahead - if you are thinking about changing feeds or getting in new hay make sure enough of the old feed is saved to make the switch.

   • Lock the feed room door.

       Overconsumption of non-structural carbohydrates (grain, commercial feed mixes and treats) will create havoc within the cecum.  The sudden influx of soluble carbohydrates will cause colic and/or laminitis.

• Be careful when a horse is on pasture.

       Even though horses are designed to eat forage and are happier when in a large field of grass, too much of a good thing can make them sick. 

          If introducing a horse to pasture for the first time, it must be done slowly.  The green forage can disrupt the microbial balance in the cecum. A horse used to a dry hay diet will have problems when suddenly turned out on pasture.

          Spring grass and fall grass after heavy rains are high in soluble sugars.  Horses must be gradually introduced to this type of forage.  Some horses may have to be limited on the time allowed to graze or may not be able to tolerate the lush new growth at all. 

• Observe your horse after de-worming or administering drugs.

        If your horse is on an antibiotic or has been de-wormed, some of the microbial population may have been killed.  A probiotic may help restore the cecum to its natural healthy balance of bacteria and protozoa.

    • Do not feed moldy or questionable feeds.

       If it smells, looks or feels funny - don't feed it.  The toxins that may be present will make the horse sick.  It's safer for the horse to go without a meal than take a chance.

  • Provide fresh clean water at all times.

        Ponds, streams and water from run-off should not be used for drinking water.  Fertilizers, herbicides, insecticides, bacteria, and other forms of contaminants can be present.  All of these foreign invaders will upset the cecum.

       When feeding or watering your horse you are actually feeding the unseen cecum.  Keeping it healthy and happy will help keep your horse healthy and happy.

    * For information about nutrition and horse care take the online courses Nutrition For Maximum Performance and Stable Management taught by Eleanor Blazer. Earn certification or work toward a Bachelor of Science degree in equine studies.

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Eleanor Blazer