Non-structural Carbs and Horses
By Eleanor Blazer
          It’s no laughing matter.

          We make jokes about our horses being over-weight.  They look like Thelwell ponies or we can’t keep a saddle on.

          Are we killing our horses with kindness?          

          Weight and insulin problems are on the rise. 

          Feed and supplement manufacturers know horse owners are looking for an easy way to control these problems. Look in any horse magazine and you will see advertisements for products that contain low starch, low sugars, low carbohydrates; will help burn fat, or lower blood insulin levels.

          But, just like their owners, who have the same problems, horses need to eat right and exercise.  There is no quick and easy fix.

          Do the terms Equine Metabolic Syndrome, Cushing’s disease, peripheral Cushing’s, insulin resistance and hypo-thyroid sound familiar?  The common symptom shared by of all these conditions can be obesity.

          To determine if an obese horse has one of these syndromes blood tests need to be taken.  Contact a veterinarian.  Even if the over-weight horse tests negative weight control, nutrition and exercise must be addressed to avoid future problems.

          The hardest part is taking weight off the horse.

          A term every horse caretaker should know is Non-Structural Carbohydrates (NSC). 

           There are two basic types of carbohydrates: structural and non-structural.  Structural carbs are fiber; non-structural are sugar and starch.  Excessive amounts of sugars and starch lead to weight gain.

          The non-structural carbohydrates must be reduced in a diet designed for the obese horse.  Most hay testing laboratories do not test forages for NSC and it is not required on a feed tag.

          In addition to this, there is no standard method of measuring NSC levels.  So, if one manufacturer uses one test and another uses a different test the products cannot be accurately compared. Even within the same lab variations, can occur.

          How does a person know if the product is a safe choice?  At this point the NSC levels are not on the feed tag.

          Oats, corn, barley, and molasses contain high levels of non-structural carbohydrates.  Most commercial horse feed rations contain these ingredients. 

          The obese horse does not need oats, corn, barley, molasses or sweet feed.  He does need vitamins, minerals and enough protein to meet his daily requirements. 

          If the horse tests positive for one of the syndromes it is even more critical he gets vitamins, minerals and good quality protein, because his overall health will be compromised.  But he still needs to loose weight.

          Most feed companies now offer products that will meet those requirements. "Ration balancers" are excellent sources of vitamins, minerals and protein without the non-structural carbs or added calories.

          In addition to offering a product that meets the daily nutrient requirements without non-structural carbohydrates the forage quality and quantity must be addressed.  Hay and pasture can be a source of non-structural carbohydrates.

          This can be a challenge.  Horses need forage in their diet.  They are grazers and their digestive systems need the structural carbohydrates (fiber) the forage provides.

          Despite the accuracy challenges of testing hay for NSC levels, it is the only method we have for estimating NSC content.  But, what if you have 500 bales of hay that are high in non-structural carbs….burn it and start over?

          Luckily starch and sugars are water soluble.  Soaking the hay for at least sixty minutes in hot water or thirty minutes in cold water can decrease the non-structural carbs in hay.

          Pasture can also contain high NSC levels.  The time of day an obese horse grazes is critical.  The sun pulls sugar and starches in to the plants leaves and the levels peak in the afternoon.  Grazing before noon may help. The use of a grazing muzzle may also be needed.

           For more details about feeding forage to over-weight horses or horses that have insulin problems visit

           It is also important it limit the amount of forage the over-weight horse consumes.  You can't cut out all the forage, as the equine digestive system needs fiber to work properly. Horses need to have at least 1.0 percent of their body weight in forage in order to maintain a healthy gut.       

          As in all weight loss programs exercise is important.  In addition to taking the weight off it also helps lower glucose levels.

           If you have an over-weight horse in your barn, now is the time to take action.  Don’t wait until he develops laminitis…you may lose him and that is no joke.

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