Decomplexicating Equine Nutrition Part 09 of 12 – GMO, Pesticides and Fertilizers

GMO Foods and Their Use In Horses

Here we are in the proverbial space between a rock and a hard place. Farmers want to be efficient and create the largest yield of production to increase the profits of their business while the consumers of the food want to be fed the cleanest and healthiest food possible. Can these two possibilities coexist?

What are GMO foods? These initials stand for “Genetically Modified Organisms.” The exact definition is dependent on the country and the organization using the term but simply put, a food that is produced from an organism that has had its DNA (the genetic code that makes the organism) altered by scientific engineering is a Genetically Modified food. In the United States, it is most likely involved in the crops that make the most money such as soy, corn, cotton and canola. The genetic modifications make the plants more resistant to disease and to applied pesticides both of which create a healthier plant and thus a larger yield at harvest. There are some genetic modifications that cause the plant to produce its own pesticide, some that delay ripening and some that increased the nutrient value.

GM was first used in 1983 to help tobacco plants grow. in 1988, microbes were genetically modified leading to the term GMO but in 1994, the first genetically modified food was created – a tomato modified to delay ripening and have a longer shelf life. Since then, in the United States, tens of thousands of genetically modified plants have been tested in the field. In the 1990s the papaya industry in Hawaii and in China was saved from a virus through GM. Potatoes, apples and squash have been modified for various reasons. Today in the US over 90% of all soy, corn and sugar beets including their products are genetically modified.

Animals fed genetically modified foods have no evidence of it other than some small biologic effects that had no consequence on the tested animals. Yet consumers find GM foods a threat to the health of animals and to humans. I believe the reason why most GM foods don’t cause disease is because the genetic modifications are changes done to the proteins of the plant. As we have learned, proteins are broken apart by the acids in the stomach into individual amino acids and those are absorbed through the gut wall in the small intestine before the hindgut bacteria have a chance to see them. In other words, the modifications made to the genetic code are forming new proteins with different amino acid sequences, but in the digestive system, all protein is broken apart and destroyed, modified or not. Hence there have been no diseases found in any animal directly related to GM food.

With this said, due to marketing and health food advocates, foods that have been genetically modified are usually avoided. The primary reason is that this new technology has had no long-term health studies on humans or the effects on the environment such as the effect of altering the balance between species. Unfortunately, in my practice, soy has carried the brunt of this yet is a tremendous source of a wide variety of amino acids for horses. Interestingly, almost all sugar beets have also been genetically modified. After all the sugar has been extracted for human use, the leftover pulp, with all the genetic modifications in the associated proteins, is used in horse feed.

Yet the question still remains about the safety of GM foods. Many countries including the US give blanket approval for many types of GM foods while other countries such as the EU require case-by-case approval. Still, other countries outlaw all GM foods. There is little consensus because all sides appear to have an agenda that contaminates their research and published findings. The final decision may not be evident for decades to come. In the meantime, I see other more important present issues such as carbohydrate dependency, chronic protein deficiency and lectin-caused gut inflammation. If you do not want GM food for your horses, then avoid all grains and byproducts because they have all been genetically modified.

Pesticides and Fertilizers Use On Foods For Horses

Pesticides are chemicals that kill pests (any word ending in “-cide” means to kill: homicide, suicide, bactericide, insecticide). While we generally think of chemicals applied to the food we feed horses, the hand sanitizers Americans have become addicted to are also pesticides in general thinking. Most plant pesticides kill predators including pathogens (bacteria, viruses, fungi), vectors (flies, bugs, birds) and predators (animals that eat them). The problem with pesticides is that the residual pesticide can be ingested by the horse and cause an illness or even death. Further, when washing off these chemicals, they enter the groundwater affecting everything they touch from ground microbes, earthworms and the fish in the nearby streams.

A classic example of a pesticide that was also used as a deworming medicine is the class of compounds called organophosphates. These were usually administered on a clear and sunny Sunday morning in the springtime when horse owners would deworm their horses. I would then be called for the field of colicing horses an hour later. It was classic.

Fertilizers are elements applied to plants to enhance their growth by supplying needed nutrients. These include nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, copper, iron, manganese, zinc and a few more. Don’t these sound familiar? Aren’t they in the pills we take and in the food we eat and feed our horses? Maybe not the nitrogen but that comes in with the air we breathe (80% nitrogen) and the proteins we eat.

Organic fertilizer is made of natural materials such as animal waste and sewage. Inorganic fertilizers are chemical compounds that do the same job as organics but either are more concentrated or they have additives that prevent any runoff from being toxic to the environment. Agriculture runoff of fertilizer is a major problem in freshwater ecosystems allowing for overgrowth of algae fed by the fertilizer. The algae were otherwise normally kept in balance and the growth of all things in the environment is regulated by checks and balances between organisms.

All fertilizers can upset the natural balance of the land the food is grown upon. Adding nitrogen may acidify the soil decreasing its ability to provide needed nutrients. But this is easily countered with pH testing and adding lime to buffer the acid.

Sources of these added elements in agricultural fertilizer, for example, zinc, can be from uncleaned industrial waste. It is very expensive to clean this waste making good clean fertilizers more expensive. An example of a purified fertilizer is Miracle-Gro used within houses throughout America filled with children and pets. But contaminated waste used in agricultural fertilizer may include toxins such as arsenic, lead, nickel and cadmium.

Research into whether fertilization depletes the soil of trace minerals (iron, zinc, copper, magnesium) has resulted in determining that it does not. Rather, it is the improved crop yield per acre that is causing this depletion. In fact, these types of fertilized foods actually have lower mineral concentrations than the ancestral foods farmed before them. Throughout the world, missing elements such as zinc are added to the fertilizer which replenishes the missing elements of these modern crops.

While the use of organic waste seems a little better for fertilizer use, the byproducts of all nitrogen-based fertilizer are the third leading gas in the global warming debate behind carbon dioxide and methane. As horse owners, we need to realize that most of the food including the hay has been fertilized either organically or not. There is really no advantage to using organic fertilizer when it comes to the health of your horse. In fact, there may be some mineral deficiencies if only organic fertilizer is used. However, using feed from crops fertilized inorganically with non-purified ingredients may have toxic effects from unwanted elements. What is the solution?

Are GMOs and Pesticides Important Considerations?

The answer to this question may lie in something most scientists are not considering and that is what I have been saying from the beginning of these blogs on nutrition. When you feed your horse, you are NOT feeding it but instead, you are feeding the bacteria within the gut – the gut microbiome. These are the guys affected by the pesticides and possibly from GM foods.

There is a pesticide called Roundup (glyphosate) discovered by Monsanto and now, off-patent manufacturing is done by many companies worldwide. It is an herbicide and a desiccant (drying agent) used to kill weeds within a crop to decrease competition for nutrients for the crop. In addition, Monsanto genetically modified the crops so that they resisted Roundup and were not affected. The first crop that was “Roundup Ready” were soybeans. All studies that have been accepted by government regulators worldwide have not found any health risks to Roundup generally in humans with the exception of some eye damage when directly applied and to aquatic life. What this means is that within certain acceptable limits, this pesticide and the genetically modified plants resistant to Roundup do not cause direct harm to humans or to other farm animals.

Glyphosate is also used as a drying agent on many crops not modified genetically to get the product to market faster. Therefore just because a food is non-GMO does not mean that they are free of this chemical. Glyphosate is also relatively friendly to the soil and in a different formulation, better for aquatic life. In fact, even earthworms have been studied and soil bacteria – seem OK with this chemical. But few if any studies have been done on the gut microbiome.

If the hypothesis is that all diseases come from an altered gut microbiome then a determination needs to be done on the effect of all pesticides and GM foods on the gut bacteria. If it has been proven that one Prevacox in horses can wipe out a whole family of bacteria in the mouth, then what are these treated and modified foods doing to them? Has a new crop of bacteria evolved that enhances health, hinders health or has no effect on the health of horses?

When looking at diseases of horses, many causes are found such as an increased level of insulin in the blood called insulin resistance. The root cause of this has not been accurately determined but it is associated with just about every case of laminitis. Add to this mystery the factors of stress, grain overload, obesity, pituitary function, dopamine levels and other causes and where is the real cause located? Could it be as simple as good gut bacteria being replaced by bad gut bacteria? Is this caused by feeding grains or feeding genetically modified grains and hay or grains and hay treated with glyphosate? Maybe it’s a combination. But as horse owners trying to do the best for our horses, we need to eliminate as much as possible and start feeding our horses the basics they have lived on for millions of years – pasture and water. Adding hay to this is necessary. Adding protein is beneficial. If these added things have genetic modifications, I would not worry. If they have been treated with glyphosate or other fertilizers then I probably would not worry either though there is always the choice of feeding organic hay and soybeans.

Simply ask yourself these questions. Are there any recorded cases in horses of disease, dysfunction or malaise due to feeding GM foods? Or feeding foods that are grown with pesticides that were properly handled? I don’t know of any, yet when horse owners stop feeding grain and byproducts and add extra protein, these horses start to thrive. The hay and protein sources are all genetically modified and most likely have had Roundup applied. While GM foods and added chemicals are in the mix of potential causes of diseases in horses, I think the root cause of disease lies elsewhere.  Feed the horse correctly, allow the gut bacteria to normalize and watch the health of the horse improve while eating less.  Eating less means eating less GM food and foods with applied chemicals.

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  1. I have seen 2 documentaries about this. One said roundup ready makes the pests’ stomach explode. The other was the plight of Roundup ready seed that was grown in India and causing a myriad of disease and deaths in cattle as well as the farm workers that consumed their corn. As soon as they removed them the diseases subsided. India has outlawed Monsanto products finally. Also, please don’t rely on big pharma based studies claiming no harm from anything. Remember when 4 out of 5 doctors recommended Pall Mall cigarettes? And when Aspartame was safe? There were many papers that were fraudulent and had false information. Look who funds the studies.
    I really enjoy your articles, but please look into this a little deeper. 😊

    1. I am acutely aware of marketing and how they have deceived us over the decades. Smithsonian‘ s “The Real Mad Men of Advertising” goes into this from the 1950’s and The Howdy Doody Show. I am not a spokesman for big pharma. I am skeptical of most research and was trained at Cornell for 2 years how to read research papers correctly. I also look to see who is behind documentary films as they are usually expensive to produce and distribute. As the Wall Stree Journal reported 2 or so years ago, the number of retractions in medical journals is at a all time high with tenure being the most common reason for fudging data. If you want to look at where research papers are currently, Google “The Parachute Study.” Most importantly, I think.

      I understand your focus on glyphosate. It is made by 7 different companies and Monsanto has been purchased by Bayer providing pallets of Round Up available in Home Depot.

      However I want to focus on the real issue here and that is carbohydrate dependency, mitochondrial exhaustion and the subsequent chronic protein deficiency. Whether someone chooses to use soybean meal or use only organically grown forage and feed is not as important to me in the short run as removing the inflammatory ingredients and restoring the missing amino acids. The diseases and lamenesses prevalent today are real for many people while no one is seeing the untoward effects of glyphosate in their horses. Purchasing organic forage and feed and having pure pastures is not available to most horse owners today. If a horse owner has access to this then I’m sure they would choose it if affordable.

      I eat organically when the option is available but life on the road is not usually accessible to it. If there is a market with organic food I then look for non-inflammatory oils, no lectin based foods, and grain free foods which cuts out over 90% of the food at Whole Foods even in their eatery.

      All we can do is the best we can do with what is available. We need to help people become aware of the downside of glyphosate but scaring them into not removing the grains or supplementing the lost amino acids will never get their horses back. What is the point of being glyphosate free when their suspensories are breaking down, the hind fetlocks drop, they have kissing spine, they have laminitis or a myriad of hoof diseases, immune dysfunctions, neurological dysfunctions and colic all stemming from gut inflammation and protein loss? This is the position of this blog. To be clear, glyphosate is likely altering our gut microbiome as well as the soil microbiome. But I also believe in hormesis where the bacteria become tolerant to this former antibiotic as most bacteria do. Antibiotic resistance is the primary concern of the CDC here in America. Could this also be happening to glyphosate even when it remains an effective broadleaf herbicide? The full story has yet to be told but for now, horses removing inflammatory grains and grain byproducts and adding soybean meal are seeing tremendous positive results.

      I truly appreciate your comments here as there are many with the same thoughts. I hope this gives an alternative view acceptable to everyone.

      1. I absolutely believe in the no grain diet and love your blogs. All of my horses are on this diet and are doing wonderful! I am an equine body worker and I see the effects of a grain diet daily. I have your blog info on my home screen of my phone because I give it to all of my clients. They report very good results from performance horses to backyard pets.
        I am happy your response has a more “the jury is still out on glyphosate and gmos”. I agree we can only do the best we can for taking care of our horses (and us). I know my hay grower uses gmo seeds but honestly my horses are doing so much better grain free even with the gmo hay I don’t worry about it.
        Thank you for your blogs! And responses!

        1. And my sincere thanks to you for sharing so much of this with your clients. I am grateful beyond words.

  2. Monsanto has now lost multiple law suits that were filed due to RoundUp (glyphosate) causing cancer. They have been fined billions and there are thousands more law suits pending trial for the same. You need to read more and watch videos by Institute for Responsible Technology. RoundUp is NOT harmless to people or animals. Even WHO acknowledge it as a probable carcinogen years ago. In regards to the gut biome, glyphosate was first patented as an antibiotic, and as you know, antibiotics destroy the gut biome, so there’s the answer to that question. I have enjoyed learning much from your blogs, but this one really fell flat and disappointed me greatly. Time to update your knowledge about RoundUp and let people know how dangerous this really is to us and our animals. We feed our horses only organic grass pellets and have them on pasture the majority of every day, only bringing them in for daily care or work and their grass pellet meal. The pastures are not sprayed with fertilizer or pesticides or herbicides. They are both in excellent health. The other barn mates that feed grains and keep them all day in their stalls do not fair nearly as well as our girls. You give a lot of good advice and information, but not this time. Do a little more research please.

    1. Thanks Melissa for bringing up these points. The case about glyphosate did bring a verdict for billions of dollars but the case is being appealed. The cancer is being found in the inappropriate application of the chemical and not in the ingestion of it. This is why the verdict is being challenged.

      As far as I know, there are about 7 makers of glyphosate in the world. While the case against Monsanto was being litigated, the giant company Bayer bought Monsanto. If they thought it was a problem the sale would never have occurred.

      Also as far as I know, the World Health Organization (WHO) has recently lifted its ban on glyphosate and now recognizes it as being safe when used as directed. I do need a citation for this but my source is credible.

      I acknowledge that glyphosate was developed as an antibiotic. The most damage then would be seen in the microbiota of the soils of the plants where it is applied. The half life is about 120 days and for this reason I wonder if glyphosate is active in our food. Of more interest is the question that if glyphosate is so destructive then in a world where it is found everywhere (including organic products) then why do we see little if any disease directly attributable to it? Could our cells and our gut microbiota through hormesis be adapting to it?

      There are so many factors causing the myriad diseases affecting humans and horses and it is possible that glyphosate is one of them. However from my perspective there are other factors more influential that we can have more control over. For example; continuous feeding of sugar throughout the year in the form of starch in grains and forage, feeding of lectins in grains and grain byproducts, the overuse of non-essential medications (sedation use to replace horsemanship), the chronic protein deficiency in horses and the abundant misinformation about feeding horses.

      The purpose of this blog was to counter the rhetoric about glyphosate. In my mind it may be bad though there is little day to day evidence that our gut microbiome can’t handle it. But for those not able to keep their horses on chemical free pastures or without access to organic hay (the majority of the horses today), the larger concern is feeding grain and grain byproducts every day of the year. What this is doing to humans, horses and all pets is astounding. By reducing the use of grains the amount of glyphosate will also be reduced PLUS the horses will become healthier and happier. Isn’t this what we all want?

  3. I have been telling horse people about the feed they are giving their horses. Some listen, but most do not. They think the feed companies would not do that. I tell them the feed companies are just trying to make a dollar, no matter what the cost. Thank you for helping us keep our horses healthy and happy.

    1. You are very welcome and thank you for trying. I find that the best question to ask anyone doubting is this: “How is what you are doing working for you?” If the answer is good, then don’t worry and talk about the weather. But most will admit to behavior problems, digestive problems, lameness or hoof problems or a feed room full of supplements, a complex feeding schedule and no money left over to fix the barn roof.

      Thank you for being the horse’s advocate.