carbs in horses diet

Question
I have a warmblood that is allergic to wheat, oats and barley.  I am wondering what another good source of carbohydrates would be.  I'm not really keen on corn.  How would beet pulp be?  Someone suggested buckwheat, what type of buckwheat would be the type to buy? Peas were another suggestion. What about rice? how would you suggest preparing rice?  One other suggestion is Amaranth, which I'm not familiar with.  Can you give me the best choice without spending $100.00 per bag?

Answer
Hi Kerry,

Thank you for your question.  Carbohydrates can be classified as either non-structural or structural in nature, with each type having its own energy characteristics.  The non-structural carbs (NSC), or starches and sugars from cereal grains and plant cell contents, are digested in the stomach and converted quickly to glucose (energy) in the bloodstream.  Structural carbohydrates, the fiber component of feed, are fermented by bacteria in the hindgut of the horse and converted to volatile fatty acids (also energy) in the bloodstream but at a lesser and slower rate.  

So if your horse needs lots of energy from carbohydrates, cereal grains are generally the best source.  With an allergy to wheat, oats and barley, your horse is limited to a lesser number of starch sources.  I agree with you about corn in horse diets, I'm not a fan.  Having said that, when there is little other choice, steam flaked corn would be the only alternative I would consider.  It will be more expensive that unprocessed corn but the steam flaking process helps greatly improve the digestibility of the corn...and makes it almost as digestible as oats.  My concern with buckwheat and amaranth would be both price and digestibility.  They are more expensive, both grains would require processing to render them digestible by the horse and even then buckwheat would not be very palatable.  I can honestly say I have not had any experience in feeding rice (other than rice bran) to horses as an energy source and as such can't help you with how it may be prepared but I would think it could become expensive to feed large quantities to horses.  Again, your best choice may be steam flaked corn.  Some feed stores will carry the steam flaked corn by the bag, while others may be able to source it from their parent companies (as it is often included in calf feeds and high end sweet feeds).  

If you are looking for carbohydrates to bring energy to the diet, perhaps you could also consider feeding more vegetable fat in the diet as it too will provide energy.  Fat is 9 times more energy dense that carbohydrates, although the body does take a little longer to transform it into usable energy.  If your horse is not in very heavy exercise, fat can often provide a significant portion of the exercising horse's total daily energy requirements.  Some people will top dress with straight vegetable oil (soya, flax or canola oil are much better than corn oil) or you can feed a high fat supplement like rice bran or milled flaxseed (which is very cost effective).  If those products are difficult to source, soybeans would be a nice alternative as they are high in fat, protein, fermentable fiber and have some NSC content.

If your horse is not in very much work, you may be able to source really good quality fiber (structural carbohydrates) to provide enough energy in the ration.  Beet pulp would fall into this category...the horse's digestive system will ferment it like a fiber, but it more fermentable and will convert to more energy more quickly than even the best quality hay.  You can, in fact, replace a significant portion of the horse's grass/hay diet with beet pulp.

I hope that helps sort out your dilemma.

Thanks, Corlena