Chronic Protein Deficiency In Horses

This is a very important article for all horse owners to read and understand.  I know that a lot of horse owners don’t have time to read this, but I promise you that reading and understanding this article will be life-altering for your horses. If your horses are lame, if their top line is melting away, if skin disease plagues them, ask yourself why. Then read and understand why I think that most horses have a chronic protein deficiency. Doc T

The Basics Of Protein

Look at this sentence. It is made up of words and each of those words is made up of letters. There are 26 letters from which all the words are made and all the written thoughts in the books of our world are ideas expressed by the combinations of these words. 26 letters, enormous vocabulary, and infinite written ideas.

Taking this one step further, look at the variety of books, magazines and newspapers in the world. All appear different and are made of different materials, yet all have sentences, words and letters. This is how all the things on this planet are made if you think about it – even you and your horse.

Books, magazines and newspapers are made up of a few basic parts: paper, cardboard, ink and glue or staples. Our body and the body of our horses are made up of 6 basic parts too: gas (air), water, minerals, carbohydrate (sugar), fat and protein. Of these, protein is the most interesting because all proteins are made up of only 20 building blocks called amino acids. Consider these letters. These amino acids make up all of the proteins of the body. Proteins are like words in a dictionary made of a finite number of letters, yet an enormous amount of information can still be expressed through unique sentences depending on how many words are used and where we place them.

Letters make words that in turn make sentences that create unlimited thoughts. Amino acids make proteins that in turn make structures that create unlimited living things on our planet.

Proteins basically provide the structure that makes us and every living animal we know into their unique shapes through the connective tissue of bones, ligaments, tendons, and muscles. They also make up a lot of other things in our bodies including defense mechanisms, sensors, and hair. I know this is basic, but I really want to get a few points across about protein in our horses.

Our alphabet is divided into two groups: the vowels (a e i o u) and the consonants (all the other letters). The amino acids in your horse are also divided into basically 2 types: non-essential amino acids (NEAA) and essential amino acids (EAA). This is VERY IMPORTANT. The difference between them is that NEAA’s can be made by the horse but the EAA’s need to be consumed pre-made in the meal. Imagine your book had only consonants (NEAA’s) but was missing some but not all of the vowels (EAA’s). The result would be a book that was hard to impossible to read.

If the diet of a horse doesn’t contain enough of the EAA’s then the horse will be deficient in many things such as connective tissue and immune function leading to lameness and skin conditions. Like a book missing some of the vowels, the horse may look like a horse but he will not work properly.

NEAAs can be made from carbon, hydrogen, oxygen, sulfur and nitrogen consumed in normal foods and the air we breathe. With this in mind, have you ever wondered why cattle can graze on poor land or be fed poor hay (”cow hay”) and still do well? Did you ever see a picture of a goat on top of a pile of garbage with a tin can in his mouth looking fat and happy? The answer is because ruminants like goats, cattle, sheep, and deer can manufacture almost all of their amino acids thus they have a low requirement for EAAs. In essence, they can build most of their proteins from the molecules they consume. Ruminants still need all the amino acids a horse does but can manufacture most of them (the NEAAs) while their need for consuming the EAAs is low.

However, you and your horse cannot manufacture about half of the amino acids we need to grow and maintain our bodies. These 10 or so amino acids need to be consumed in their complete form and are therefore essential to maintaining life.

Remember, the wall of our digestive tract (stomach and intestines) is solid to large molecules such as proteins. Every protein we eat is broken down into smaller amino acid building blocks or small groups of amino acids called peptides (like syllables of words) and these are absorbed through the intestines into the body. These amino acids and peptides are transported to individual cells and assembled into the proteins required by the cell. [As a side note, think of this the next time you buy an expensive joint supplement. What you are really feeding is a high-quality protein high in EAA’s that is broken down by digestion into the basic amino acids and peptides and reassembled into what the horse needs. It would be just as good to feed your horse a less expensive high-quality protein source.]

Here is an interesting fact about EAAs. This fact I am about to describe occurs in humans and horses and once understood, will change the way you look at protein in both you and your horses.

When the minimum amount required in daily intake of just one EAA is less than 100% of what is needed on a daily basis, then none of the other EAAs will be absorbed at 100% even when there is an abundance of the other EAAs. Another way to look at this is to say that if there are not enough of the individual amino acids to build the protein, that protein won’t be made.

For example, EAA #1 requires 100 units a day and EAA #2 requires 500 units and EAA #3 requires 1000 units and so forth for all of the 10 EAAs required by your horse in a day of eating. Pretend that your horse consumes 200 units of EAA #1, 500 units of EAA #2, and 800 units of EAA #3. In this example, the horse is consuming 200% of what he needs for EAA #1, 100% of EAA #2, and 80% of EAA #3.

At first glance, you would assume that your horse is deficient in only EAA #3. In reality, mammals have a system where if one EAA is at 80% of what they need, then ALL of the EAA’s are at 80%. In this example, because EAA #3 is only being consumed at 80%, then every EAA this horse consumes is at 80% effectiveness no matter how much is eaten.

Enough High-Quality Protein

It is important that your horse consumes enough protein, but it has to be of high quality (high in EAA’s) and it all needs to be absorbed from the gut into the body.

Crude protein is the absolute amount of protein in the feed. Unfortunately, some countries add urea to the feed to increase the crude protein value making the crude protein value suspect on any product. Many countries and the UN have started to use “True protein” or to list the individual amino acids as a way to see the protein content of food. This value does NOT tell you the quality or the availability of the protein for your horse. What is needed is the biological value of the protein which is the amount of protein that will be available for absorption past the wall of the intestines and used by the horse.

Not all proteins eaten are absorbed and used equally. Some have a tougher time breaking down and being absorbed ESPECIALLY if the intestines are inflamed by consuming inflammatory feed such as grain, grain byproducts, seeds and inflammatory oils. I have talked about gut inflation in some of my other blog articles. The percent of protein absorbed is sometimes called their biological value (BV). For example, egg whites are completely absorbed, whey protein is about 96%, soybeans about 80% and grass and hay is about 50% to 65%. Also, some sources of protein also have limited amounts of EAA’s making these proteins poor sources of protein for horses.

The quality of the protein is based on the amount of EAA’s in the protein. The more EAAs in the protein, the better quality it is.

The quality of protein can’t really be measured in hay or grass because every batch of hay has a different amount. In fact, the only way to measure the total protein being fed is to measure the actual protein of the animal consuming it (killing it). Unfortunately, this measurement is not a test you want to do on your horse. A rule of thumb holds though that the better the quality of hay or grass, the higher the quality of protein consumed and the reduced chance of a protein deficiency in your horse. The more stalk in the hay, the higher the fiber and the lower the available protein. Therefore, if your pasture and hay are of poor quality and your pasture and hay are limited in quantity, your horse is probably not getting enough good-quality protein. They ingest enough protein to live, but do not live well enough to become athletes.

The Simple Solution Is To Add High-Quality Protein To Your Horses’ Diet

Proteins in mammals don’t last long. The average life span of a protein is about 1 to 2 days. They degrade into parts and are recycled or destroyed and excreted. They can live for a while, such as through the winter, without consuming good quality protein but at some point, they need to replenish what has been lost. Otherwise, a chronic deficiency will occur which is the main thrust of my message here.

Horses in the wild consume a lot of good quality and live forage with good quality protein in the natural habitat during seasons when it is available. When winter comes and forage becomes dead or scarce or covered by snow then the recycled proteins are used. It holds them over until the spring grass returns. The protein shortage in the wild has a backup plan that gets them through tough times until good protein can return to the diet.

In my experience with horses kept by humans, they usually don’t have access to a lot of pasture. Worse, access to good quality hay is limited by many factors including the age of the hay, the way it was harvested, and the distance from the source. In fact, most barns have poor-quality hay and it gets worse in the spring just before the new harvest is cut. If the horse can’t get access to good quality sources of protein year after year, then your horse could be suffering from a chronic protein deficiency. Specifically a deficiency in the proteins requiring the EAAs.

It is a chronic deficiency because I have been with horses since 1973 and today I see more horses having so many medical issues that did not occur 40 plus years ago. Lame horses are at an epidemic level now followed by skin issues, insulin resistance and pituitary dysfunction (Cushing’s). While vets now have tests and diagnostic equipment for these issues, no one is looking deeply for an answer to why they are occurring in the first place. Only superficial answers are given such as the intense show schedule, poor footing, genetics of today’s horses, poor training, etc. While all of these may be a factor, I still believe there is a deeper underlying cause for chronic protein deficiency.

If the body is constantly breaking down protein just from the process of living (called entropy), it needs the building materials to repair itself. Add to entropy the additional wear and tear from movement and work such as jumping, galloping, collection, explosive starts and stops, endurance, and more. Where are the building blocks for repairing bones, ligaments, tendons, and muscles? Where are the proteins necessary for hormone and receptor creation, immune system charging, systems processing, and more? Proteins are essential for everything in you and your horse’s lives and if you don’t get enough protein and their EAA’s and the reserves are used up, my hypothesis is that the horse will become sick, lame or both.

Another analogy may help explain this. If I delivered to you all the lumber you need to build a house, what house would you be able to build if I didn’t supply the nails? In essence, every horse being used for work or sport is stressing the muscles and other connective tissue in the process. Building this stronger structure is called conditioning the horse but requires the horse to have the materials to repair and strengthen the muscles, tendons, and ligaments. This material requires all the amino acids and especially the EAAs.

My solution is simple and I would love to get everyone to start and then record their results. Add high-quality protein to the horse’s daily intake, record all your observations, and be patient. Adding protein will require between 4 and 6 months to see the beginning results with maximum results in a year or two. You are basically rebuilding every cell in your horse’s body. And by supplying the necessary building blocks in the EAAs, then everything will be repaired and strengthened.

An interesting fact here is that one bacteria cell has about 2 million proteins. A human has about 1 to 3 BILLION proteins in EACH CELL. A protein in a yeast cell is made of about 466 amino acids but some muscle proteins in humans are called titan proteins because they are made of almost 27,000 amino acids EACH. Next to water, proteins are the most abundant molecule in the body. Are you starting to see the enormity of the situation?

Is My Horse Consuming Enough High-Quality Protein?

The best indicator of good quality protein consumption is the topline because this is made of muscle only, which is almost all protein. There should be enough muscle on both sides of the spine to fill in the hollow otherwise seen in a poor top line. The Nutrena® company has created a “Topline Score” – TLS. The back is divided into 4 sections and labeled with the letters A, B, C and D. It is interesting to note that the loss of topline in a horse always starts at the withers and progresses towards the croup (hips). Conversely, the withers is the last area to be filled in after increasing protein consumption.

The TLS goes like this:

  • A – all the topline is filled with muscle.
  • B – All the topline is filled with muscle except for the withers.
  • C – The croup and loin is filled with muscle but the saddle area and withers are not.
  • D – Only the area over the hips has muscle and the rest of the top line is absent.

Old horses often have a TLS of D with or without a sway back which I believe is predominately a chronic deficiency in protein. I am suspicious of the painful condition of kissing spine as a sequela of a poor and weak topline due to chronic protein deficiency and collapse of the spine tips upon one another.

I want to add a TLS of F often seen in very old horses.  The added sign of muscle loss is the absence of the masseter muscles (cheek muscles or jowls) leaving only the flat bone of the mandible.

The Body Condition Score – BCS – was created to judge the fat on horses. BCS 1 is a walking skeleton and BCS 9 is fat enough to float in water. A BCS of 5 is ideal but is not descriptive enough. For example, if a pasture horse has a BCS of 5 and a TLS of C, the owner would be told by others that the horse is underfed and encouraged to add weight (body fat). But a racehorse with a BCS of 5 AND a TLS of A would be called an athlete just like our human counterparts.

Most trainers exercise the horse to improve the TLS but think again of the barn building analogy. The lumber is there (the horse) and there are plenty of carpenters ready to pound nails and build the barn (a training or conditioning system). But without the nails (EAAs), no barn is built (the horse breaks down).

If excessive poor quality protein (without the EAAs) is consumed, then the production of required protein in the body is curtailed. However, the protein not used in the diet is then consumed for energy creating urea, a byproduct of the nitrogen loss in all the amino acids being converted into glucose (gluconeogenesis). If you smell ammonia in the urine, it is because your horse is consuming excessive amounts of poor quality protein, is inadequately making the proteins necessary for body maintenance and growth, has a poor hair coat and hoof, has a poor TLS, may be lame, may have skin conditions or is unthrifty and the urine and barn smell like ammonia.

Where Do Horses Get High-Quality Protein And What Exactly Should They Be Eating?

Horses in the wild consume a variety of forage (grass, leaves, and other vegetation) and they consume it throughout the day. This is not the case with horses in captivity on poor or little pasture and suspect quality hay. With this in mind, I want to go deeper into the discussion of amino acids because there is more to understand before you can help your horses. Stay with me.

I said that there are about 10 EAAs but you might say so what? Horses in the wild must get them so why not just turn them out in a big field? You might also say that your horses basically look good and are performing well enough. In essence, you would be right – for most horses. Because of the sub-clinical effect of chronic protein deficiency, you often won’t see its effect until it is too late (lameness) or the horse ages and the topline is lost. Because this deficiency is possible in most horses fed by humans, it is necessary to learn about the 3 “Limiting Amino Acids” (LAAs).

The LAAs are the EAAs that are found in limited supplies in nature. They are lysine, methionine and threonine. Looking at the 3 limiting EAAs and what they do in the horse will help you understand why it is important to give enough high-quality protein to your horses every day.

  • Lysine – promotes bone growth in foals and maintenance of the connective tissue (bones, joints, tendons, ligaments, etc) in mature horses. A deficiency may cause a variety of developmental orthopedic diseases in the legs of young horses and in adults may cause the breakdown of suspensory ligaments, tendons, joints and other structural components.
  • Methionine – growth and maintenance of hair coat and hoof structures. A deficiency often causes a poor hair coat and poor hoof quality (cracks, crumbles). See more below.
  • Threonine – overall growth, muscle mass maintenance, production of adrenaline and other important hormones. A deficiency often causes poor body condition, poor TLS and lack of energy.

You might recognize methionine because it is often added to hoof supplements. It is one of 2 EAAs that have sulfur in it. Sulfur has the ability to attach to the sulfur of another amino acid with a sulfur molecule and this is called a disulfide bond. This bond causes the amino acid to fold upon itself and become structurally stronger.

Now that I told you this, let me say that methionine doesn’t create disulfide bonds. Confusing I know, however, the methionine is converted into cysteine and then cystine not only has strengthening provided by the disulfide bonds but makes up about 24% of the protein in the hoof. Without methionine, cystine cannot be made and cystine is the biggest player in hoof integrity. It is considered by some that the inflammation in the laminae (laminitis) causes the breakdown of the disulfide bonds which causes the coffin bone to separate from the hoof wall. Another hypothesis would suggest that providing enough protein, specifically methionine, would help prevent laminitis as well as hoof cracks and poor hoof quality. This is why methionine is added to hoof supplements. However, to be effective, there must be enough of all the EAAs to create, maintain and repair all the proteins of the hoof. Remember that while 24% of keratin is cystine, the remaining 76% is still protein. However, with a deficiency in the limiting amino acid methionine in the natural diet, and subsequent deficiency in cystine available with their disulfide bonds PLUS the deficiency in other EAA’s, the hoof will struggle to maintain itself against the rigors of shoeing and training.

A sidenote – when a farrier applies a hot shoe to the hoof, the stink made is from the release of sulfur.

If your horse is prone to laminitis or has poor-quality hooves, it may be valuable to add a high-quality protein source. While I can see no downside, it must be remembered that it takes a year to grow a new hoof so adding protein won’t fix a deficiency right away. But the sooner you start, the sooner the horse will have a solid hoof.

Lysine is critical for almost every protein in the horse (and you) because it helps to make the other proteins available for use. Without lysine, the remaining amino acids and proteins just aren’t as abundant to do their jobs. Lysine is the number 1 limiting EAA and it is often not available in large enough quantities in grass and hay. Lysine is the FIRST key to unlocking protein efficiency and supplementation and is essential for horses kept in our care today.

What Protein Should I Feed And How Much?

The simple answer is from ½ to 1 gram of protein per pound of body weight depending on the needs of the horse (1 to 2g per kg).

Let’s do some math. If you are feeding a pound of grain with 10% crude protein in it then how much protein is your horse getting? 1 pound = 454 grams. 10% of 454g is 45.4g of protein. Because this is crude protein, we need to determine the true protein source. If it is alfalfa meal, oat hulls, and other assorted vegetable protein sources (read “by-products”), then we need to divide 45.4 by 2 (50% availability) which equals about 23g. Even with this knowledge, if you can’t determine exactly what amino acids are in this, then this 23g could be deficient in the LAAs and other EAAs.

Your 1000-pound horse is also consuming protein in the hay and pasture, but how much and of what quality? If a horse eats about ½ of a 40-pound bale of grass hay a day, then he is consuming 20 pounds or 9080g. Good quality grass hay has about 10% to 16% crude protein – let’s use 16%. 16% of 9080g is 1453g. Now crude protein needs to be digested and the biological value of grass hay is about 50%, so half of 1453g is about 725g. If the goal is to consume 0.5g to 1g of protein per pound of horse per day (500g to 1000g per 1000 pound horse), then you are right in the middle at 725g from hay plus 23g from the pound of grain (748g).

But are you really? Remember the 3 limiting EAAs that are often missing in a natural diet – lysine, threonine, and methionine. Add to this that you are using your horse for athletic purposes requiring conditioning that is building connective tissue. Then is 748g of suspect quality protein enough? In my mind, every horse needs to have added to this diet an additional source of high-quality protein that is found in soybean meal and whey protein isolate because they add the missing EAAs, and specifically the LAAs.

Continuing with this horse, let’s increase his requirement to 1g of protein per pound so we want 1000g of protein. He is about 250g shy which can be achieved by adding 266g (0.59 pound) of whey protein isolate (94% absorbed). You will need 312g (0.69 pounds) of soybean meal at 80% availability to also achieve this goal. From this additional protein, you should have enough EAAs and LAAs to prevent the consumption of fed protein for energy (urea production) and to build the proteins necessary to prevent the problems of chronic protein deficiency.

There are several commercial products containing soybean meal or whey protein isolate in combination with minerals, vitamins and a carrier base. Be careful of the carrier base as it is often corn and byproducts. When I started working with horses in the early 1970s, we had a bag of straight soybean meal and we added a scoop (I can’t remember how big but maybe a quarter cup) once a day.  I recommend only using the ingredient of soybean meal or other high-quality protein but I do NOT recommend any of the complete feeds of soybean meal mixed with grains and grain by products, vitamins or minerals.  These mixes will actually cause gut inflammation in most horses and will prevent the horse from using the high-quality protein in the mix.  Again, there are many protein mixes and “balancers” but beware because most of these products have “various vegetable proteins” as a source combined with soybean oil (inflammatory and added as a machine lubricant), corn (inflammatory) and molasses (unnecessary and inflammatory).


First of all, I am not affiliated with any company nor do I sell any supplements or protein products. I only want to create a conversation and develop thoughts that will inspire you to think and start making better decisions in keeping your horses.

Second, if your horse has any health issues then consult with your veterinarian first.

My recommendation is to 1) stop feeding sugar (grain, grain byproducts and all supplements including treats, carrots, sugar cubes, apples etc.), 2) increase pasture and good quality hay (grass and some legume) consumption, and 3) add 1.0 pound of soybean meal to the daily intake for your horses weighing  1200 pounds (545 kg) (1000 to 1400 pounds or 454 – 636 kg).  Have unlimited access to water and mined salt (rock salt or Himalayan). Further, I highly recommend starting a diary to record every possible observation and commit to this diet and chart for a year. If you want, after a year, write a summary of your observations and send it to me with permission to post and help me get the message out.

Remember, if you don’t like the results you are getting you can always return to your original diet. No harm was done.

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  1. Hi and thanks for that article.
    I’m a bit confused about the part that says that poor topline is sign of not enough protein? If a horse is not doing any work, or doing very basic work, she/he wouldn’t have a “good” topline?

    1. Ask any body builder if exercise is all they need to build muscle. In other words, If I deliver a truck load of boards (Forage) and a bus full of workers (exercise) to build a new barn for you, it would never materialize without nails (protein).

      But it is not just about having too little protein in the feed. The MAJOR point is the insidious loss of protein from the carbohydrate dependency and the subsequent mitochondrial exhaustion leading to gluconeogenesis (the conversion of protein into sugar. The horse converts ALL proteins into sugar to save the body including the muscles of the top line, the quality of the hair and hooves, the neurotransmitters (Cushing’s), the immune system and more.

      Horses NOT in work but are removed from inflammatory grains and byproducts AND are supplemented with soybean meal improve their top line. They also lose their hay belly and strengthen all connective tissue and hooves – all without added ex cerci seems.

    1. I think all “balancers” and “hay stretchers” are brilliant marketing doing 2 things. They make you believe that a balancer is needed and they add ingredients to make some of the nutritional related problems worse – and making their product more necessary. I wrote about a “balancer” in this blog:

      If you want to make your horses healthier then eliminate the things that cause gut inflammation and only add what is missing (amino acids found in good quality protein) until they are no longer missing. This has worked for a very long time however it is human nature, especially in the nurturing humans, to keep adding things in the belief that something is missing. We all need to understand WHY something is missing and it is not just because they are not getting it in their food. It is because the inflammation is consuming it or the cell metabolism is blocking their use. This is behind the theory of carbohydrate dependency and mitochondrial exhaustion as well as lectin blockage of glucose uptake through insulin mimicry. While all of this sounds mumbo jumbo, I just look at the horses I see across this nation and ask, is what we are feeding working? The answer is no and adding the same ingredients you find in most of the grain mixes won’t help.

      Long answer for a short question. So the short answer – I don’t think much of any balancer or hay extender. But this doesn’t answer some people’s question of how to feed a competitive horse. I’m working on this. The answer may sound similar but with a twist. Stay tuned.

  2. Hi Dr. Tucker:

    Word is getting out! Last week, I sent a friend (who was visiting that area from Kansas) to a feed store in Southern Pines for SBM and when she asked if it was dehulled/toasted/oil-extracted, all the employees turned and looked at her and one said “do you know Allie?” Allie is a friend of mine that I told about your diet, and the feed store has had a dramatic increase in SBM sales as she shared the word in her area. My KS friend bought the last bag they had in stock.

    This week I was on a training trip in Tryon and went to the feed store there to pick up SBM while I was in town. When I ordered it, the lady said they had to vastly increase their orders of both SBM and Coolstance over the last four months because so many people have started feeding it. I know this is because of people who have heard my horse’s story and who then started the diet and spread the word. The feed store here in Aiken has also reported noticeable increase in SBM sales.

    My saddle fitter was out today and is thrilled by the beautiful, lean muscling on my FEI horse and the healthy condition and lack of hay belly on my 21-year-old draft cross. She was interested in the diet and your theory on chronic protein deficiency and kissing spine, so I sent her that blog post. She responded “Awesome! Thank you! Man, I’m working on a horse right now that looks just like the picture from the article! How do you go about telling people about this without sounding like you’re criticizing the way their horse looks?! 😬” She’s going to use my horses as an example and suggest your blogs.

    My vet was out last week to do spring shots and Coggins and was thrilled by what she saw. The 22-y-o horse who had a huge hole in his check ligament six months ago now looks fantastic on U/S and sound, far exceeding our original conservative expectations, and she credits the protein supplementation as an important factor.

    Thank you again for your generous help. I credit your ideas with saving my partnership with my very talented FEI dressage horse. Not one explosion or moment of dangerous behavior in the six months on The Diet, and not one drop of gastroguard or ulcer treatment. He is lean, muscled, strong, and working very well. Getting closer to that GP debut!

    1. Thanks for this testimony! Sharing it here will help those hesitating to try this program – then they in turn will share their stories and we will ALL learn together.

  3. Thank you for your response Doc T. I’m still trying to figure out how to keep obesity at Bay, and not doing a very good job for for years now. Trying different things. I have been under the advice of a well known nutritionist since 2014, but something must be missing. Or I’m doing something wrong. Probably not enough exercise. I’m 77 and my mare has been fighting a limp for about the same time. So I haven’t been doing much with her. My age, her feet… Haha..

    1. Obesity in fat mice can be resolved with a fecal transplant from thin mice. This verifies that it is the gut microbes in charge of weight. Focus on removing gut inflammation, allowing for the good gut microbes to reestablish, and be sure to add a variety of protein to the diet to replace lost protein materials including the hormones that control appetite.

    1. All proteins have a shelf life after which they are broken down into their individual peptides or amino acids. The exception are hair, hooves, finger nails, etc that are lost to the environment. The average half life of most proteins is 2 to 4 days but neurotransmitters are only nanoseconds old before they are disassembled. The amino acids and peptides are then recycled and made into new proteins.

      Think of a game with small blocks of letters organized into words. At the end of the game the blocks are shuffled about into single blocks and reorganized into new words in the next game. A peptide is like “-ing” which can be used as in park-ing or jump-ing.

      In gluconeogenesis, the amino acid is stripped of its nitrogen and the remaining carbon, hydrogen and oxygen are turned into glucose. The chronic loss of the amino acids leads to a chronic deficiency in proteins. But if gluconeogenesis is limited, the amino acids are preserved and recycled into new proteins. Horses who have restored their supply of amino acids through the addition of essential amino acids in their diet will not need to be supplemented as much. Remember though that the hooves are 24% cystine which is made by the horse from methionine, one of the 3 limiting essential amino acids required in its diet. As the hoof is worn off the protein is forever lost.

      Remember also the concept of a limiting amino acid. In the wooden block letter game, you could have 20 w’s, 20 a’s, 8 c’s, 22 t’s and 30 h’s. With these letters you can only make 8 “watch” words because the limiting letter is “c.” After this you can make make 12 “what” words. After that you still have 2 “t’s” and 10 “h’s” which can make no real words. This is the concept behind feeding a broad spectrum of amino acids and enough of them if your horse has been depleted of amino acids.

      You can learn this and more from some of the other blogs and from the nutrition course here at The Equine Practice. Unraveling the confusion created by layers of experts and marketing is my goal here. Having people like you reading and asking questions makes this journey very rewarding. Thank you. Doc T

  4. Can you recommend any suitable protein feeds available in the UK? I cannot find either of the ones you suggest in your article 🙁


    1. The concept is to supply an assortment of protein ingredients. Soybean meal is excellent and economical for horses. Whey protein isolate is very good and a great addition to soybean meal. Adding a flake of alfalfa a day as well as good pasture and hay should be considered the basic starting point. Avoid soft seeds as a protein source due to the potential lectin reactions in some horses.

      There are many protein supplementing products available. All you need to do is research and read the ingredients. In Louisiana a feed manufacturer is now producing the “Doc T Mix” – shredded alfalfa and a soybean pellet. Great results there.

      Note that supplementing at 0.5 to 1.0 gm per pound of body weight is good for helping horses depleted in protein but as the top line and other indicators of normalized protein are seen then this target can be reduced. This is when the protein recycling program takes over.

      Read all the blogs or enroll in my upcoming nutrition course. And thank you for finding me and asking this great question.

  5. I just heard about your blog, Dr. Tucker. What is your opinion on a product called “Equinety?” It is made up of 8 amino acids…We have one horse on this that suffers from anhydrosis, and I would like to put my horse that has had laminitis for two spring/fall seasons in a row. Thank you.

    1. I can’t remember all the products so let’s look at some protein facts. Any continuous feeding year round of starch (grains) will inflame the gut and prevent the absorption of amino acids. Addition of any acid reducing medications will prevent the absorption of all proteins. The hoof is made of proteins and specifically 24% is one amino acid (cystine which is created from methionine) while the remaining 76% are a combination of other amino acids.

      In a blog called No Sweat I discussed the observation that anhydrosis can be resolved by removing all grain from the diet. I suspect lectins and gut leakage that is somehow disrupting hormone communication but this is only conjecture.

      Removing grain from the horse’s diet should help resolve the sweating issue as well as allow for digestion of proteins and absorption of amino acids. Removing all starch will also ease the strain on insulin, reduce the excess fat, stop gluconeogenesis (absorption of top line protein) and help prevent lameness including laminitis.

      To recap, adding an amino acid supplement or a protein supplement may be ineffective as well as wasting money if the chronic sugar dependency (feeding grain every day)is not stopped. Please read all the blogs (more coming) on nutrition here:

      1. I need to apologize for not mentioning that we own a horse boarding stable, all 14 horses are on Coolstance and a vit/mineral supplement with free choice hay. The horse with anhydrois and with laminitis has been off grain and on Coolstance for 7 years. Coolstance is made up of about 17 amino acids, but the % is minimal in comparison to the Equinety, so my thinking was maybe more amino acids will help his anhydrosis. Thank you for your quick response.

        1. For the horse with anhydrosis, remove all food except for hay, pasture and water. No supplements, Coolstance or treats. Nothing but grass and hay and water. If the sweat starts, then don’t add anything for a week or two to be sure all is working well. Then add back only one thing at a time.

          It is NOT a lack of protein but some ingredient in the coolstance or the vitamin mix that is disrupting the hormone in sweating (a lectin maybe?). Simply put – remove all potential causes before adding things. In the experience of so many who have tried this elimination, almost everyone gets their horses sweating again on the no-grain (and no supplements) challenge.

          1. I appreciate your knowledge…the horse with anhidrosis, we removed all food as you recommended and he began to lose weight, but he still did not sweat. We had a vet perform acupuncture on him in July and put him on Chinese herbs, and remarkably he began to sweat; a week later we lost him to colic (twisted colon). Needless to say, we were devastated.

          2. I am so sorry for your loss. We still don’t understand anhidrosis but I am suspicious of gut inflammation which every horse handles differently. I wish we knew more. My thoughts and prayers go with you and all horses suffering from seemingly untouchable diseases. Some day we will understand.