Decomplexicating Equine Nutrition Part 01 of 12 – Grazing Not Browsing

Browsers are people who stand in front of the refrigerator with the door wide open looking for something – anything – to eat. Right?

Actually, there is a difference between a grazer and a browser technically. Horses are grazers and ruminants (cattle, deer, sheep, goats, and many more) are browsers. Let’s look at each.

A very long time ago every specie developed a way to feed themselves. The idea was to take things that surrounded them and eat them to create the needed energy to survive and reproduce. It is a simple concept and one I really can’t understand. Why can’t we just face the sun and drink some water? No, we must kill things and eat them. Thankfully most humans don’t worry about being eaten and in this country, horses are somewhat safe. The cow, pig, sheep? Not so lucky. Same with the plants we eat which are also killed for consumption. So are the plant’s babies (seeds) but more on this later.

We all have a tube running through us that starts at the mouth and ends at our anus. You and me, the horse, the dog, – you get the idea. Every one of these tubes has developed a distinct way to digest the foods around us. The ruminants have won the “best-in-class” award because they can eat woody things called lignin. This includes twigs, bark, saplings and other stiff plants. They can also make almost all of the proteins needed to survive and grow. This is why you can see ruminants living in the poorest conditions and surviving and often thriving.

Horses on the other hand cannot digest lignin. What they are very good at is digesting cellulose which is like lignin but not as robust. Cellulose is found in the cell walls of all plants grown on land. It is made up of a sugar called glucose. Making up the sugar storage of the plant is starch. Without having to know organic chemistry, I want to tell you exactly what starch and cellulose are.

We need to start with one molecule of glucose, the most common sugar. Each molecule is made up of 3 different atoms: carbon, hydrogen and oxygen. We will call these C H and O in the future. Through the magic of chemical energy, C H and O connect together in a simple pattern of a 6-sided ring or hexagon based on 5 C atoms and 1 O atom. For a visual, think of a stop sign in the shape of an 8-sided ring or octagon and pretend it has 6 sides. Around this ring are 12 H and 5 O atoms but don’t worry about this now. Just pretend you are looking at a 6 sided stop sign and think of this as one molecule of glucose. There are other variations and combinations of this structure that make up the other sugars such as lactose and fructose but we want to talk about starch and cellulose.

Take one “stop sign” or glucose molecule and attach it to another molecule of glucose using bonding glue. Now your visualization looks like a “stop-stop-stop-” string of glucose molecules. Keep going and add a thousand glucose molecules together. stop-stop-stop-stop-stop-stop-stop-stop-stop-stop-stop-stop-stop-stop- and so on for thousands of units. This is what starch is and you and your horse can digest starch using our enzymes breaking it down into the simple sugar glucose.

Starch – the glucose molecules are strung together in the same position.

Now bond your glucose molecules so that every other glucose molecule is upside down. In the 6 sided stop sign it would look like this: stop-sʇod-stop-sʇod-stop-sʇod-stop-sʇod-stop-sʇod-stop-sʇod-stop-sʇod-stop-sʇod-stop-sʇod- and so on. This is cellulose and another word for this is fiber.

Cellulose – the glucose molecules are connected with every other molecule upside down.

What is necessary to understand is that you and your horse can NOT break the bonds of cellulose using the enzymes we have. In fact, no animal can digest cellulose. What we all have are bacteria in the colon (large bowel, hindgut) that CAN break up cellulose into individual glucose molecules. But because it is an inefficient way to get energy, the horse developed a very large hindgut and a set of teeth to continually harvest enough grass and other forms of cellulose to get the energy it needs to survive the day.

Ruminants on the other hand can eat both cellulose and lignin. Lignin is like cellulose with the addition of an alcohol unit which the rumen bacteria break down. The ruminant then pushed this mix back up into his mouth and re-chews the material (chews the cud) and swallows it again this time bypassing the rumen and heading back for the regular digestion that is similar to the horse.

The take-home message is that horses developed specific anatomy for digesting cellulose and because of this, it is the primary way a horse should eat. Grass, therefore, is the ideal food along with other non-woody plants and leaves (ground plants). This does NOT include seeds such as wheat, oats, barley, chia, sunflower, corn and any other seed you can think of. These seeds contain starch which is a simple sugar and not cellulose. The bacteria in the gut of the horse become unhappy when simple glucose is presented to them, not in cellulose form. Other bacteria start to take over and can be considered “bad” bacteria because they are very efficient in taking the starch and converting it to sugar giving the horse a high sugar diet.

But wait! Don’t the “good” bacteria break down cellulose into glucose molecules too? Isn’t this also feeding the horse sugar? The answer is a solid NO!

I leave you hanging on that because it leads into the next article. But simply put, starch is broken down into simple sugars killing the good bacteria and causing lots of problems in the horse including insulin resistance. Cellulose is NOT broken down into a simple sugar but into something you will not believe (hint: it makes energy). Stay tuned!

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  1. My horses, one being a 23 year old gelding, are on a grass & hay diet with the exception of a handful of steamed crimped oats in the morning and some ground flax seed….they look so forward to this every morning…is this really a bad thing?

    1. Hi Shelly – What is the purpose of the flax seeds? Where do horses find flax seeds year round? Many people add flax seed for the “oils” and the shiny hair coat, but in reality if you want this then feed a source of broad variety amino acids. The cellulose from the hay gives the horse the fats he needs for nutrition and oils but the amino acids of the hair itself is what makes the hair coat shine. In fact it is the first thing most horse owners notice once they stop feeding grains and add protein – usually in about 2 weeks.

      A handful of oats in any form usually dose not harm a horse. Crimping does not improve digestibility as it is the normal gut microbes that digest them. Seeing oats in the manure is NOT from a chewing issue but from a gut microbe dysbiosis. Steaming may actually remove the lectins especially if the oats have been dehulled (“cleaned”). Remember that according to Dr Gundry in his book “The Plant Paradox,” in a human study in 1932 (yes 87 years ago) the cause of cavities in children was found to be oatmeal. Where did that study go?

      What you are feeding still does not address the chronic protein deficiency which from this diet I would assume they are having. Please read all the articles to understand why chronic protein deficiency in horses is seen everywhere. Be sure to read ALL the comments under each blog to hear from others that have changed the diet. Also join the Facebook private group “The Horse’s Advocate” to interact or search for more on these subjects. Thanks, Doc T

      1. The purpose of feeding the flax seed is for the horse to get omega 3’s in their diet. they don’t get this unlesss they have pasture.

        1. There is no doubt that having a broad variety of living plants in pasture is perfect for all horses. And most horses today have limited pasture or have a mono-grass pasture.

          I am having trouble finding where omega 3 fatty acids are lacking in any horse. What are the signs of a deficiency in horses? If cellulose is converted into short chain fatty acids by the hind gut microbes and the hind gut microbes are healthy, then is there a need to supplement with any omega fats?

          Hay is last year’s summer grass. Would this be enough for the omega fats? Is there an optimal 3 to 6 ratio? Are these needs for supplementing omega fatty acids extrapolated from human medicine or have there been good quality studies in horses (not funded by anyone with an interest in the outcome)?

          Finally, if flax seeds are truly needed by the horse then for how long are they needed? Where and when do horses get flax seeds in the wild?

          I have so many questions that are not being answered. But what I am finding are horses around the world removing grain, grain byproducts, supplements and treats and adding a broad variety of amino acids all responding so well to this protocol. And still no signs of vitamin, mineral or fatty acid deficiencies either before or after starting this protocol.

          My mind is still open and I really appreciate you bringing to our attention the things you are aware of. However if you could cite some GOOD references for the importance of omega 3 fatty acids I would love to read it. We all want to get this right. Thanks, Doc T

          1. I agree horses in the wild wouldn’t be eating fax seeds but when your horse only gets hay and never any pasture how are they going to get their omega 3s?

          2. Hay is last year’s summer pasture. If kept properly and fed within a year there should be enough cellulose to make the fatty acids the horse requires.

            The questions to ask here are: Where do horses get their omega 3, 6 and 9 fatty acids (FA’s)? What are the importance of these FA’s in horses? What are the signs of deficiencies in the omega FA’s? What are the normal ratios of FA’s in horses? I’m sure there are other questions but from what I can find in horses, the only advocates of adding omega FA’s to horses are makers of FA’s or producers of foods exposing their FA content.

            Is anyone looking at any inflammatory effects of flax in horses? There are some reports of inflammation in humans from flax and chia seeds. Remember seeds are not a normal staple of humans or horses when looking at 1) the 100,000 years homo sapiens have existed, 2) the seasonal availability of seeds in the human or horse diet and 3) the effects of concentrating seeds into a feed versus the less dense availability when found naturally on the plant. And of course there are the lectins of all seeds which are causing leaking gut in humans. Is it possible it is causing leaking gut in horses too? This is behind my hypothesis of the cause of EOTRH in horse incisors.

            So many questions and so few answers. Ugh!

          3. Here is what I wrote about EOTRH and it’s cause –

            Lectins cause autoimmune diseases in humans and the world’s leading expert on horse teeth believes that EOTRH is an autoimmune disease. While you don’t see EOTRH in humans you do see dental decay. Dr Gundry cites a 1932 study linking dental carries with eating oatmeal. Dental decay and fracturing of cheek teeth in horses was not in the text books in the 1980’s when I was in vet school. Fractured cheek teeth is a new development since, you guessed it, the feeding of grains became popular.

            Food for thought. Just waiting for a researcher to grab this and work with it. Until then we can only hypothesize.

      2. I give them about 2 oz of ground stabilized flax seed for the omega 3…their hoofs never crack and always look good, barefoot….why do you say their diet is lacking in protein.?…they are on pasture 24/7 with a couple flakes of hay in the morning this time of year, along with a small amount of oats. I also give the older horse a lb of nutrena topline performance balancer dailey

        1. While you did not mention any signs with your horses, I am assuming that “pasture” in most people’s circumstances is one or two types of grasses or mixed with weeds they don’t eat. If there are an abundant variety of grasses then I stand corrected and I apologize for assuming otherwise.

          If a horse eats about 20 pounds of hay and / or pasture a day and the protein content is about 12% then they will be consuming about 1.2 pounds or 545g of protein (½ of 12% = 6% and .06 x 20 lb = 1.2 lb and 1.2 x 454 = 545 g protein). Protein is about 50% bioavailable. If the minimum amount of protein in a horse is 0.5g per pound and an average horse weighs 1200 pounds then the need for that horse is 600 grams. 545 is just under the minimum amount.

          HOWEVER….. what is missing here is that the hay is most likely not filled with all ten essential amino acids. If there is one limiting amino acid then there are a bunch of proteins not being made. Think of writing a sentence using words from a dictionary missing one letter. No “W” and there is no who, what, why, when or tomorrow. You cannot make the sentence “Where will we meet tomorrow?” All you can say is, “Meet.” So a diet in a closed pasture with a limited type of hay, in my mind, is deficient in some amino acids.

          Add to this the usual addition of inflammatory ingredients (grains (seeds), carrots, apples, treats, supplements, and inflammatory ingredients found in ALL “balancers” plus the daily carbohydrate intake (carbohydrate dependency) and you have the mechanisms for gluconeogenesis that turns proteins into carbohydrates. This is the cause of muscle wasting, connective tissue failure and illnesses we see as the horses and humans get older. Go to the mall and look at the 60 to 90 year olds wasting away, sick or both. It is all from protein loss with no additional proteins added to replace these lost amino acids.

          From what I am seeing as I travel to farms all across this country, protein loss is far worse than a lack of omega fatty acids as I have not seen a case of a horse suffering from low omega 3’s. As cellulose is digested into short chain fatty acids by the hind gut microbes, the fatty acids should be adequate.

          All your horses are young including the 23 year old. Factoring in their genetics and the love you obviously have for your horses AND the abundant pasture, you will probably never see the signs chronic protein loss. However because this is a public blog and people from around the world see these comments, I must respond in depth so that others may learn from your questions. For you asking them I am very grateful because there are other just like you wanting to ask the same questions. Thank you!

          For more info on proteins, carbohydrates and fats please read all the blogs at and especially all the comments.

          1. So, if i cut out the oats. ,ground flax seed and the balancer, what form of amino acids do i feed them along with hay and a semi weedy pasture that we do manage (fertilize, lime, aeriate and dailey manure removal)

          2. Soybean meal. It has a complete amino acid profile and is 80% absorbed. As a legume it is fine to feed to horses. As a temporary fix to the chronic amino acid loss, you don’t need to worry about GMO and glyphosate though you can find organic soybean meal.

            Please read all my blogs at There are several blogs on protein there.

            Thanks for asking this question.

          3. Where can you find soybean meal? I believe you recommended something with coconut, where can you find that also?

          4. Every region in the world has a story about finding SBM from easy to impossible. There is a surplus of soybeans in America but not everyone makes it into a meal. You just need to do the work in your area to find it. If you need to go a distance for it so you nd up getting several bags at a time remember that rodents love SBM. Place all bags purchased in rat proof containers.

            Go to the Coolstance website ( to locate a dealer near you. Several horse farms have become dealers.

          5. The molasses is unnecessary and is inflammatory. All SBM has a flow agent so that can’t be avoided. Keep looking for dehulled, oil extracted soybean meal with nothing else added except a “flow agent.” This prevents it from caking into chunks and has no bad effect on the horse.

          6. Ok….will keep looking….i figured the molasses wouldn’t be good.

            Can i just feed some good quality alfalfa for now along with grass hay and pasture for now….having a hard time finding soybean meal here in TN….may be able to find some whey tho

          7. Yes you can do this especially if you have adequate summer grass with a variety of species. The results will come slower but as long as the inflammatory feeds have been removed, the loss of protein will be a lot less.

            Platinum Performance has a product called Equi Whey which is a “low lactose” (low sugar) form of whey protein. Whey protein isolate is much better as all sugars are removed but is more expensive. Any human brand will work.

          8. Ok…will do….about how much whey dailey?…1000 lb horse, just pasture horse

          9. Because the bioavailability of whey protein is about 15% more than SBM, you would need to feed about 15% less. 1 pound of SBM daily for a 1000 to 1400 pound horse would then be 0.85 pound whey protein isolate per day. Unfortunately I do not know the difference in bioavailability between isolate and non-isolate protein but I would guess it is close. However there may be some inflammation from the sugars in non-isolate whey.

          10. Gonna start challenge this weekend….with a pasture, grass hay, a little pure alfalfa and water diet….my question is , can you just stop giving the grains all of a sudden? Or should you do it gradually ….grains are crimped oats, balancer and 1 oz dailey of ground flaxseed that i feed

          11. The simple answer is yes. I have not had anyone complain that their horse or horses had an adverse reaction to the sudden withdrawal of any inflammatory food. Rather the horses quickly show signs of reduced inflammation such as sweating in hot weather and calmness in the barn.

            If someone was allergic to gluten such as a celiac patient, would you gradually taper off the gluten or would you remove it as quickly as possible? It’s like when people ask me if floating the teeth of horses (removing the sharp points) is painful. I answer that I am removing the cause of the oral pain and that the horse was painful up until the floating.

            To my knowledge, all horses do well with complete withdrawal of grains and supplements and treats at one time with the following exception. Many who expect to be fed paw the stall door and create a ruckus. This lasts about 3 days then miraculously stops. If you are bothered (or YOU are having withdrawal) then toss in some hay cubes into the feed tub. The horses will be happy. And if you are concerned about no more treats then feed 1 or 2 peanuts in the shell for a treat. Most love this.

          12. Ok…will just give them some quality afalfa in their stalls in the morning which i have already been doing gradually….they sure do love it…lol and will cut out the grains….is watermelon rinds ok?

          13. No, watermelon rinds on a daily basis is not ok. But if once after a weekend bar b q then it shouldn’t matter. Just don’t call me if they colic cause you gave them 20 pounds of rinds.

          1. Ok….will keep looking…i cant afford to buy it online….only have 2 horses …..

  2. So are you saying we should give our horses Chia seed. There has been so much written and products for horses stating that Chia seed is better than flax seed as an omega 3.

    1. I’m not sure where you thought I said any seeds were OK for horses. I also have not discussed oils such as omega fats. What I am saying is that cellulose is converted into short chain fatty acids as explained in part 2. What those become is interesting.

      The primary source of energy in horses is cellulose. In addition, all the fats and vitamins start here. The biggest problem for all horses (and all humans) is a continuous year round supply of carbohydrates. Understanding this principle is essential for the health of horses (and humans). Stay tuned for more.

      1. Sorry, what I meant to say is we should not give our horses chia seeds then? I have been giving my horse ground flax seeds but I have also read that chia seeds were a good source of omega 3’s for horses.

        1. Chia has the good 3’s and are low in the bad 6’s – in humans. Not absolutely sure about horses but keep in mind that removing inflammatory feed far outweighs the addition of supplemental things. Also remember that if the horse’s good gut bacteria are restored and fed correctly then they will produce the short chain fatty acids needed to create the required fats to reduce inflammation and increase energy. Lastly, removing the constant work load of daily overdose of carbohydrates will help to restore healthy mitochondria – more on this in a bit….

  3. Greetings Doc T – all three of my boys are thriving mentally and physically on “no grain” feeding program. We are beginning week 5.

    The TB is almost – and I stress almost – docile to ride. The older WB (22) who had recurring, runny stools no longer has the issue. The other WB could eat rocks and he would be unaffected.

    Keep ‘feeding’ us good science in ‘digestible’ bits.

  4. I am a green owner of an Arab 25 and pony 12. I started your grain free challenge and haven’t gone back. My equine have energy for playing and great looking poop. No coughing. They are moved between 2 areas for forage and a pasture were working on. They get orchard grass hay too. You’ve helped affirm my instincts where my horse and pony are concerned. Thank you!! They are steadily svelt and have remained so all winter. They drink fresh water from heated buckets. Saved the Arab from a colic last winter because I didn’t know about cold water…he survived and I still have no vet. Just a fan Farrier.

  5. Another great post explaining the “why” I should be feeding my horses forage. Your chemistry lessons make so much more sense than the school textbooks. Based on your postings, we removed the grain from our horses feedings and now give them forage and hay — they are calmer since we have done that. I do have a question – is beet pulp considered cellulose? We have a 28 yo that is a hard to keep weight on him and it was suggested to feed him beet pulp. Keep up the great work!

  6. Hi Doc T, I feel terrible. I’ve been feeding 2 cups of black sunflower seeds, 2 cups of Renew and 2 cups of Enrich Plus ( balancer ) per day to a mare that has chronic Lyme disease and a history of founder, cresty neck etc… She has horrible shaped front hooves that curve shortly after it grows out of the coronary band and has flat soles and high heels. I’m assuming you suggest that I test the hay that I feed also. The last batch that I acquired was 2nd cut timothy. A vet that I used years ago said second cut orchard grass is good for her but no one sells it where I live. Also, I’m wondering if you recommend any farriers in north east PA? I will not euthanize unless she has no hope and I believe that she does. Thank you for your articles!

  7. It’s difficult to wait for the next pics of the puzzle!! But, question… I know my hay analysis shows the amount of lignin, however I’ve don’t think I’ve noticed cellulose on it.

  8. Here, where I live in the southwest there is no grass. There used to be real good prairie grasses, but when the white man came ,he wanted to starve out the indigenious peoples here & totally destroyed the fragile native grasses through over-grazing, & burning. Hay is substituted, but anothet problem w/ that is, all so-called pastures, & hay fields here are flood -irrigated. That’s the worst way to water plants, for when the water recedes, all the silt,& sand is left on the leaves, & stalks. Which leads me to my 2nd. pet-peave: Alfalfa hay. Cattle can barely handle it, & horses scour even worse on it. Good pastures are great, but don’t forget about the worms! Because, most people won’t clean-up manure on a daily basis, now worms are resistant to ALL current anthelmintics. So the point of my rantings is grass is good if you know how to properly care for it. Unless of course, you want to feed worms!

    1. Remember that the worms need to climb up the grass shaft. And the best parasite control is what our parents did with us. They cleaned the environment (septic system), washed our hands and made us use forks. Preventing the lips from touching the feces is the BEST parasite control with anthelmintics a poor second.