Dieticians Boast Healthful Benefits…What About Your Horse?

The nutrition industry is beginning to understand what role fermentation, gut bacteria and gut microbiome play in human and animal health. Science has just scratched the surface and is beginning to understand the activity of the microorganisms in the digestive tract and the mechanisms of action related to those microorganisms and food choices.

Fermented foods are gaining attention in the human nutrition space, but what  does that mean for our equine companions? Increasing amounts of research studies are suggesting fermented foods have powerful health benefits ranging from promoting gut health, controlling inflammation, and providing other healthful experiences. “Fermented foods” are being emphasized by registered dieticians as something to not ignore in food selections. So, how do we share these benefits with our horses without inviting them to eat Kombucha, yogurt, avocados, sauerkraut, and pickles?

A balance of good quality forage as the base of the horse’s diet and a feed concentrate that includes fermentation metabolites is key to maintaining healthy gut flora and a strong immune system. You might be asking, how do I know what is an effective and beneficial fermentation product? And how do I know my feed or balancer concentrate contains this?

I have invited a guest writer Christine W. of Diamond V to share more information and some supporting science regarding fermentation metabolites.

“Fermentation metabolites produced by Diamond V are unique, bioactive compounds that work naturally with the biology of the horse to strengthen and empower the immune system, support digestive tissue integrity, and promote a healthy microbial community.  Hundreds of these compounds are produced from a proprietary anaerobic fermentation process of Saccharomyces cerevisiae and work synergistically inside the animal to help them perform to their full genetic potential.  

These compounds help the horse’s immune and digestive system function normally in face of the many stressors and challenges, specifically hauling, training, breeding, herd dynamics, and environmental factors.

In other words, this specific species of yeast, produce several products or compounds that are beneficial to the microbiome in the horse’s hind-gut.  When the horse’s gut is working optimally, everything from digestive to immune function is set up to be resilient in the face of stressors and challenges that might otherwise compromise animal health and performance.”

Fermentation metabolites benefit your horse’s digestive tract by supporting a healthy gastrointestinal microbiome. The millions of little bacteria that live in the digestive tract all have names and each one ferments complex carbohydrates resulting in volatile fatty acid production. These acids impact digestion, absorption and the overall gut health. On a feed label you might see yeast culture listed (or S. cerevisiae extract). When fermented by the horse’s microbiome, these specific S. cerevisiae yeast culture metabolites have been shown by to support tissue strength and integrity, contribute to a stable hind-gut pH and support a healthy gut microbial community as well as a balanced immune response when challenged by stressors.

So why is improved tissue strength, integrity, and digestive health important to horses?

Horses with a strong digestive tract are better able to absorb nutrients from the foods that they eat. Research has shown that harmful substances are less likely to permeate the gastrointestinal cellular wall. Think of it as closing your screens on your windows to keep bugs out of your house, but to allow fresh air and good things to flow in. Horses need to have a strong gut to absorb amino acids, fats, vitamins, minerals, and other nutrients, and prevent unhealthy bacteria or harmful substances from getting into circulation and causing problems. By absorbing the good nutrients and getting rid of the potentially harmful substances horses are more likely to perform to their full potential. Their immune and digestive systems are supported to handle the challenges that come with hauling, training, and just being a horse in changing environments.

This article was written with collaborative authors Heidi A., Emily L., and Christine W.

Amino Acid Requirements for Horses

In order to fuel, repair, and recover muscle, equine diets must optimally contain a superior amino acid profile, including all 10 of the essential amino acids. Most horse owners can quickly name the crude protein level in the feed they provide their horses. But, what horse owners really need to know about is the amino acid content. Protein is made up of amino acids, similar to how a chain is made up of links. There are two basic categories of amino acids: Essential and nonessential. Essential amino acids must be provided in the diet, as the horse cannot create them on its own in the digestive tract, where the nonessential amino acids can be made.

Another key point is that some amino acids are known as “limiting” amino acids. This means that if a horse runs out of this type of amino acid, it can’t utilize any of the remaining amino acids present in the feed. If the horse has enough of the first most-limiting amino acid, but then runs out of the second most-limiting amino acid, it can’t use the remaining amount of the third most limiting, and so on.

In horses, the first three most-limiting amino acids, in order, are lysine, methionine and threonine. Generally speaking, if these three amino acids are present in sufficient quantities, the ingredients used also provide the remaining amino acids in sufficient quantities. It is increasingly common to see these three amino acids listed on the guaranteed analysis of horse feed tags, as it is an indication of the quality of the protein sources and the balanced nature of the feed.

If you are looking for a feed that may help impact topline, be sure to look at the guaranteed analysis on the feed tag. In specific Nutrena feeds – SafeChoice productsProForce products, and Empower Balance– the amino acid levels are called out and guaranteed on the tag. The amino acids included in Nutrena’s Topline Balance products are included in specific amounts and ratios. Research has shown that this specific combination and type of amino acids help to support a healthy topline when fed correctly.

Guaranteed amino acids on the tag is a good starting point. You then need to let the horse tell you if the feed is working by regularly evaluating and noting changes in topline condition.

To determine what nutrition best fits your horse’s needs, take the Topline Balance assessment for a customized nutrition plan.

Will Too Much Protein Cause Developmental Disorders in my Growing Horse?

Protein is a very important part of every horse’s diet.  Horses of all ages, developmental stages, activity levels, and reproductive status have essential amino acid requirements, amino acids being the building blocks of protein, and are what determine the quality of the protein.

Here’s an analogy:  consider amino acids as letters of the alphabet, and protein as words with structures such as muscle being the complete sentence.  Now put it all together; the combination of amino acids (letters) determines the quality or type of protein (word) that is formed.  The body is made up of many different types of proteins, all with distinct amino acid profiles.  If you have a shortage of or imbalance of the essential amino acids, the body cannot spell the words and complete the sentences, so the body can’t build and maintain quality tissues.

Consider this example:

  • 94% of a hoof is made up of amino acids (methionine for example)
  • The remaining 6% is comprised of fats, minerals and vitamins (biotin being just one of those vitamins)
  • Having protein or amino acid deficiency in the diet or feeding an unbalanced ration will compromise hoof integrity (brittle, soft, cracks, susceptibility to thrush, etc.).

cargill050aNow for the question above: Will protein cause developmental joint disease in my growing horse?

Growing horses have high nutrient requirements, with quality digestible protein (amino acids) being a very important and significant part of that nutrient requirement.

Confusion often occurs between providing nutrients and calories.  Providing a grain concentrate that is balanced for adult horses may provide too many calories (energy) and not enough of the nutrients (amino acids, minerals, fatty acids, vitamins ) the growing animal requires, for a couple reasons:

  1. Because unlike mature adult horses, youngsters cannot eat as much per meal (small stomach) and may never consume the recommended daily intake
  2. Because their hind-gut is immature (can’t digest/ferment forages very well) so they are unable to digest and absorb as many of the nutrients from forage as an adult horse does, leaving a nutrient gap in the total diet

The result is a mismatched calorie to nutrient ratio, with too many calories and not enough of the nutrients (amino acids, minerals, fatty acids, vitamins) that they need to grow and develop properly. High calories without the right amount and type of nutrients to support the rapidly growing animal can be problematic.  Resulting issues are often experienced as hay bellies, physitis, developmental joint disease (e.g. OCD), contracted tendons, etc.

Providing a diet balancer or a concentrate specifically designed to support growing horses is a great way to avoid the calorie to nutrient mismatch as well as provide digestible sources of those nutrients.  Diet balancers tend to be very dense in their protein, vitamins and mineral content, and very low in calories themselves.  This is why crude protein, for example, seems very high (e.g. CP 30%) in ration balancers and can cause concern among horse owners.  Fear not, feeding rates for these concentrated products are much lower than a traditional grain formula, providing all of the balanced nutrients needed in a volume that a small stomach can handle, without all of the extra energy.

Having too much poor quality protein in the diet will not be utilized by your horse, and may result in an amino acid deficiency, and makes for an ammonia filled barn due to excess nitrogen being excreted in the urine.  Having the right amount and combination of amino acids in the diet is key to supporting optimal growth and reducing metabolic waste.

Working with an equine nutritionist to find a horse feed that is specifically designed for growth and development and then following the manufacturer’s feeding directions should result in a practical and effective solution to ensure your youngster is getting the right balance of energy and nutrients, helping to avoid developmental issues and maximizing performance.

What are Essential Amino Acids in Protein, and Why Do They Matter?

Nutrition articles frequently refer to protein quality and essential amino acids. When we use the term crude protein, we are essentially talking about a calculation based on measured nitrogen. Protein is about 16% nitrogen by weight, so if we measure the amount of nitrogen and multiply it by 6.25, this gives us a measurement of crude protein. It does not tell us anything about the quality of the protein. If you tested pure nitrogen this way, it would be 625% protein!

Digestible protein is that amount of the protein that is actually digested by the animal. In an over simplified example, if you fed 100 grams of protein and measured 50 grams in the feces, the protein would be 50% digestible.

What is really important to simple stomached animals (horses included) is the content of essential amino acids in the protein. We commonly talk about 10 essential amino acids (EAA), the amino acids that must be in the diet as the animal cannot synthesize them. These are:

  • Phenylalanine
  • Valine
  • Threonine
  • Tryptophan
  • Isoleucine
  • Methionine
  • Histidine
  • Arginine
  • Leucine
  • Lysine

A common memory aid in many nutrition texts books is to use the first letters of these 10 as PVT TIM HALL. (All of you who had a non-ruminant nutrition course still remember this acronym!)

The other 12 amino acids can generally be synthesized in the body and do not need to be in the diet, although there must be a supply of appropriate substrate to produce them. Animal nutrition text books cover this topic in excellent detail.

Limiting Amino Acids
Limiting Amino Acids

When we talk about limiting amino acids, these are the essential amino acids most likely to be restricting the use of the total amount of amino acids present. In most species, lysine is the first limiting amino acid, with methionine and threonine close behind. We commonly talk about amino acids as the building blocks of protein. If you are once you run out of an essential amino acid, you cannot build any more animal protein and the rest of the amino acids are used inefficiently for energy.

If you have a horse on a diet that is calculated to have adequate “crude protein”, but essential amino acids are not present, the horse simply cannot use the protein to build and maintain muscle, hair, hoof and skin and you will see changes in the appearance of the horse, such as loss of muscle mass, rough hair, scaly hoof surface.

Feeding Oats to Horses – The Whole Picture

For decades, oats have been a staple in the feeding program of horses. Often considered a ‘safe’ grain option, there are pros and cons to this long-loved feed option. Upon closer examination, the nutrient profile of oats may surprise you. Read on and see the whole picture of oats.

Variability  – Oats are grown in many parts of the United States, Europe and Canada.  Depending on the genetic variety, growing conditions, soil type, management and harvest conditions, the nutrient content and quality of oats can vary widely.   Take for example the starch content which can range from 32% all the way up to 43%!  Variability of nutritional content can be high in oats.

Balance – Calcium and phosphorus work together to build strong bones and muscles, but they need to be in a balanced ratio to be absorbed and to work effectively.  For a horse, a ratio of 1:1 (calcium to phosphorus) is the minimum, but can range up to 6:1 and still be effective and healthy.  Generally speaking, oats have inverse calcium: phosphorus ratio and on average run 0.06% calcium to 0.45% phosphorus.

Starch level – The ‘low starch’ movement of the past decade has redefined what “low” is.  Low, being a relative term, historically may have meant anything below corn, which runs on average 65% starch.  So what is the starch level of oats?  The level of starch in oats can range from 32% up to 43%, however, the digestibility of the starch found in oats tends to be higher than in other cereal grains.  To put this into persecptive, take into consideration that ‘low’ starch feeds today run around 11-14%, and even oats are starting to look high!

Amino Acid Deficiancy – The building blocks of protein, amino acids such as lysine, methionine or threonine are required to effectively build and maintain muscle.  Though present in oats, the variability of levels is high and there are no guaranteed or consistent levels.

Digestibility – Processing oats by de-hulling, crimping, rolling, or crushing can provide a marginal increase in the digestibility of nutrients.  How much it increases, is actually minimal.  Consider this: next time you are cleaning out stalls, take a look at a pile of your horse’s manure.  See any oats in there?  Those have made it through the digestive tract without providing nutrition to your horse.

As you can see, oats are highly variable and nutritionally unbalanced in many areas important to horses.  Feeding your horse oats without balancing the diet could easily result in nutritional deficiencies.   If you feel strongly about feeding oats to your horse, it’s worth considering a commercial grain made with oats.

Alternatively, certain supplements are made to compliment oats and fill the nutrient  gaps for your horse.  This way, you can feel good about feeding your horse oats, and your horse will feel good with balanced nutrition.

Can You Feed the Flies Away From Your Horse?

In warm months, it seems like flies and other biting insects are always the #1 enemy of horses. They annoy, they bite, they cause itching, bumps, swelling and skin reactions. Often times horse owners go to great lengths to lessen the impact of flies on their horses. But can what you feed your horse actually have an impact on your fly population?

There are fly preventatives that may work for some horse owners which involve feeding a certain ingredient to the horse. Many people claim that giving apple cider vinegar daily will keep the flies away, while others swear by garlic powder or brewer’s yeast. The fact more often than not is that it is very difficult to get the horse to eat enough of these items to make a difference where flies are concerned because they typically have a strong taste and smell; the trick is getting the horse to ingest them at all. The important thing to remember is that horses are all unique and what works for your neighbor’s horse may not have the same effect on your horse.

Another alternative to feed the flies away is using a feed through IGR additive that is labeled for horses. This active ingredient does not get absorbed by the gut, but instead passes through into the manure, hence the “feed through” name. Once in the manure, the Insect Growth Regulator (IGR) causes the fly pupae to not mature into adult flies. With disciplined feeding, these products can be effective but may be expensive. One warning with this type of fly control – if you have close neighbors who aren’t controlling their fly populations you will likely see little difference because their flies will continue to come snack on your horse.

More traditional methods of fly control should not be discounted, including finding an effective fly spray, using fly sheets, and changing turn out times to when flies are less active. Cleanliness in your stable and proper manure management can also have an impact on fly populations.

In Defense of Starch

Like a celebrity on a downward spiral, starch has been getting a lot of press in the last few years…and most of it negative.  Unlike celebrities, starch doesn’t gain anything from the media exposure.  Although it may be unpopular, I’d like to take a moment to say a few words in defense of starch; a (recently) under appreciated, yet useful nutrient in horse diets.

But first, let’s start with what it is.  Starch is a complex chain of sugar molecules, which is the main source of energy for plants.  It is stored within the cell walls of the plant and therefore, considered a nonstructural carbohydrate (NSC).  Starch in horse feeds are most commonly sourced through grains such as oats, barley, corn, rice or wheat and the co-products of these grains such as corn distillers grains, rice bran or wheat midds. 

Glycemic response of oats and controlled starch diets, in horses

When ingested, starch molecules are broken down into smaller sugar molecules (glucose) that are readily absorbed. With the help of insulin, the glucose in the bloodstream is ‘picked up’ by muscles and other tissues to either be used to support activity or stored (as glycogen) for future energy needs.  Hard working and active horses need glucose and glycogen to support their activity levels and recovery from activity.   It’s also worth pointing out that NSC’s are a very efficient pathway to providing energy to the horse and to aid in muscle recovery (glycogen repletion), particularly in horses performing athletic activities.

Most horse owners know that too much starch at one time can overwhelm the horse’s digestive system.  That excess, undigested starch could leak into the hind gut where it can rapidly ferment, leading to an overproduction of gas and lactic acid, which in turn, could cause gas colic and/or acidosis which could then lead to laminitis or other issues.

You’re probably wondering, if it’s needed by horses for energy, but also potentially dangerous then how does the horse get what he needs without wreaking havoc?  The answer lies in the QUANTITY of starch consumed in each meal.

The majority* horses can tolerate a moderate level of starch each day.   This is not to say, all at one time.  There is a big difference!  Consider the digestive system of a horse to be like a waterway – it can tolerate a certain quantity of water running through it (or in this example starch) but if there is too much at one time, the water overflows and goes where it is not supposed to go.  Same with starch in the digestive system – the body can handle a moderate quantity of starch released at a controlled rate, but too much at one time (or from too big of a meal) and the whole system gets out of whack. 

I offer up one last nugget to consider: oats – the long-time staple of ‘safe’ feedstuffs for horses, actually contains approximately 40% starch. Now there’s something to think about…

So, in defense of starch, I’d just like plead the following.  When consumed in moderate amounts/meals,  frequently over time, starch is a useful and practical source of energy for most horses. 

In my next post, we’ll talk about how to evaluate starch levels in feeds.  Stay tuned for more….

*Horses diagnosed with a form of Equine Metabolic Disease (EMS) require a diet that is closely managed to control and limit the amount of NSC (including fructan from forage) in their diet.