Why are Amino Acids for Horses Important?

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. Nutrena products that include Topline Balance help to provide the right kind and ratio of amino acids in each formula.

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 products, ProForce 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.

Senior Horse Care Tips

These days, horses are living longer, more productive lives than ever before.  Thanks to advances in care, medicine, nutrition and veterinary practices, it’s not unusual to find a horse active into their thirties.  But with more active years comes the need to provide accommodations which meet the special needs of the aging equine.

Turn-out and Exercise

Senior Horse in PastureMoving is a key factor in keeping your senior comfortable.  Not only does moving about help with preserving muscle mass, motion also aids in digestion, reducing inflammation and increasing circulation.  Daily turnout is a great way to provide this opportunity, as is regular exercise.  Some ideas to exercise include light schooling, trail rides, driving or hand walking.  Whether in a pasture or dry lot, daily turnout and frequent exercise of your senior horse will go a long way in providing a happy, healthy retirement. Plus it’s more time to spend with your aging friend.

 

Dentition

As horses age, their teeth change due to wear.  Hopefully your senior horse has had the advantage of regular dental care in their earlier years, setting them up for success later in life.  Regular dental checks and floats not only help to maintain good dental health, it also provides your senior with the best chance at chewing and digesting their feed and forage.

Forage and alternative options

With the change in teeth comes some accommodation to forage.  Though aged, the equine senior still requires fiber as the main source of energy. Changes in dental efficacy as well as digestive system changes means the importance of good quality fiber is even higher.  If high quality hay (more leafy, less stems) is not readily available, hay cubes are a good alternate source of easy to chew fiber.  If needed, hay cubes can be soaked, providing an easy to chew fiber source.

Feed and Mashes

Changes in the digestive efficiency of the senior horses requires some specific nutritional needs.  As the digestive system ages, the ability to digest and absorb nutrients is more of a challenge than in earlier years.  In addition, nutrients are needed in different ratios to support the aging body.  For example, higher levels of quality amino acids are required to maintenance muscle mass in the senior horse.  Feeds that are specially formulated for senior horses provide these higher levels of nutrients in the proper ratio.  Many varieties of senior feeds are considered ‘complete’, in that they contain higher levels of fiber, providing an alternative to forage, thereby making it easier for the senior horse to get the nutrients needed.

Blanketing

You may notice a difference in your horse’s ability to stay warm during cold or wet weather.  Blanketing may be needed to help keep your senior horse warm during inclement weather.  Not only does blanketing help with warmth, your senior horse isn’t spending valuable calories trying to stay warm, burning off energy and their weight.  Blanketing in extreme cold or dampness may help your horse in maintaining a desired body condition.

Senior horse care may require some extra steps and more attention to details, but with the right adjustments, your senior can enjoy productive, happy and healthy golden years.

Tour the Equine Digestive Tract

Ever wonder how your horse’s digestive system works? What goes on in there? Why are they so sensitive? And why should I divide the feed ration into 2 or 3 feedings per day? Let’s take a closer look to better understand.

The Equine Digestive Tract:

Digestive Horse Cecum_logo

Mouth & Teeth: Teeth are the beginning of the entire process. Designed to grind foodstuffs into smaller pieces, the act of chewing also stimulates three glands in the mouth to produce saliva. These glands can produce up to 10 gallons per day of saliva. The saliva contains bicarbonate (a natural acid buffer) and amylase (assists with carbohydrate digestion). Teeth are an important component to digestion and should be checked annually to insure proper function. A horse that is unable to effectively chew long stem forage, such as a senior horse, is at higher risk of impaction colic. If you have a horse like this, be sure to consult with your veterinarian for a comprehensive care and feeding program.

Esophagus: The purpose of the esophagus is to funnel food from the mouth to the stomach. Approximately sixty inches in length, this is a one-way passage. Unlike humans, horses cannot vomit. This is why horses who ‘bolt’ their feed (eat too fast and don’t chew adequately) can get into trouble and feeding practices need to be adjusted to reduce the risk of bolting feed.

Stomach: Small in size compared to the rest of the horse’s body, food will only spend about 15 minutes in the stomach before it moves on. The stomach is designed to function best when it is ¾ full; therefore, care takers are encouraged to provide horses with a steady supply of forage throughout the day. Because of the small size, a horse should not be fed more than 0.5% of body weight in one meal. Meals of grain are best divided into 2 or 3 portions per day.

Small Intestine: After leaving the stomach, food will spend anywhere from 30 to 60 minutes here; a good thing with the many nutrients that are absorbed. Nutrients such as proteins (amino acids), vitamins A, D, E and K, calcium, phosphorus, and other minerals along with starches and sugars. Cereal grains such as oats, barley, and corn that are high in carbohydrates (starch and sugar) are easily digested here. The horse doesn’t have a gall bladder, so bile from the liver flows directly into the small intestine to aid in the digestion of fat.

Large Intestine: is comprised of the cecum, large colon, small colon and rectum.

  • The cecum is located on the right side of the horse and is where fiber is digested and converted to energy and heat. The shape of the cecum is unique because the entrance and exit are located at the top of the organ. Able to hold up to 10 gallons of food and water, the cecum contains populations of bacteria and microbes which further break down food (fiber) for digestion and absorption. These microbes are accustomed to digesting a horse’s ‘normal’ diet, so any adjustments in feed or forage should be done slowly, allowing the microbes to adjust.
    • If a horse consumes too much starch in one meal, it is unlikely to be digested fully in the small intestine. It would pass through the small intestine into the cecum where the microbial organisms rapidly ferment the starch, producing excessive gas and lactic acid that could ultimately cause digestive upset or colic.
  • The large colon continues the digestive process by absorbing additional fiber components and water. This is where B vitamins are absorbed.
  • The small colon is where excess moisture is reclaimed to the body. This is also where the formation of fecal balls occurs.
  • The rectum is where the fecal balls are expelled.

With this short tour and explanation, we hope you have a better understanding of how your horse digests and absorbs nutrients, and that this also sheds light on why good feeding management and regular dentistry care are important aspect for the digestive health and overall well-being of your horse.

Does My Horse Need a Diet or Exercise Change?

I recently taught an Equine Nutrition class to a group of seniors at an area college.  Our focus for the classroom lecture was dietary assessment by body condition scoring, weight and topline evaluation.   After the lecture I conducted a lab to apply hands on practice of what we had just reviewed.

One of the students asked if we could evaluate her horse during the lab session. The evaluation proved to be a classroom classic. The horse was a 4 year old Warmblood gelding. He was 17.1 hands and 1350 pounds. The horse at first glance appeared to be round and in good flesh, but as I ran my hands over his withers and back you could feel a lack of muscle and coverage.hand feeding red size

I asked the student what the horse’s current diet consisted of, she replied 20 pounds of first cutting hay per day and 8 pounds of locally grown oats. The calorie content of the diet appeared to be sufficient, however the amino acid balance was lacking. The student also mentioned she had her saddle recently refitted and the chiropractor out because the horse was having back issues.

With the move to college, the horse’s workload had increased and the need for additional fortification was obvious. I suggested that the student purchase a ration balancer to balance the needs of the young horse’s diet and help replenish his topline.

One of the students in the lab then challenged my recommendation.  She stated that she was an Equine Physiology major and felt my diagnosis was incorrect. She felt that by working the horse in a more collected manner, engaging his hind quarters and coming up under him would help to strengthen and develop his topline. She thought he looked fat and did not need to change his diet.

I went on to explain that the horse’s current diet was similar to a young child that would be on a straight rice diet, which is deficient in amino acids. You would see a round abdomen, but lack of muscle mass. If that child were getting ready to compete in a marathon, I doubt running extra laps would increase muscle mass, unless we supplemented the diet properly.

Again, your horse will tell you what is lacking in his diet, if you just take the time to look.

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.

Hoof Health and Nutrition

If your horse has ever had issues with his/her feet, the old adage, ‘no hoof, no horse’ could not ring truer.  When considering hoof health, multiple factors influence the state of your horse’s feet including nutrition, conformation, environment, use and overall management and care.  When assessing your nutrition program in relation to hoof health, there are many key components that need to be present for healthy hoof maintenance and growth. 

  1. Water is the most important nutrient for horses overall.  Specifically for feet, adequate amounts of water provide tissue hydration and promotes the circulation needed to deliver nutrients to the living hoof tissues.
  2. Balanced energy in the diet is important to support metabolic activity, the growth and function across the entire body system, including the feet. 
  3. Balanced proteins (aka amino acids) provide structural strength and function for hoof tissues. Lysine, Methionine and Threonine are the three most commonly associated with hoof growth.  It is imperative that amino acids be present in balanced levels along with key minerals and vitamins.  The ability for the body to absorb these critical nutrients is dependant on the delicate balance of them and too much of one or another can disrupt the utilization of these key nutrients.
  4. Macro minerals include calcium, phosphorus, sodium, potassium and sulfur.  The appropriate balance of macro minerals play a key role in skeletal development and maintenance, blood clotting, muscle contraction, temperature regulation, enzyme activity regulation, glandular secretion and cell membrane integrity. 
  5. Micro minerals (aka trace minerals) include zinc, copper, manganese, cobalt, selenium and more. Trace minerals help with the synthesis of proteins, immune system activity, synthesis and maintenance of elastic connective tissues, the integrity of skeletal bone tissue, antioxidant activity and much more.
  6. Vitamins, both fat and water soluble, play a key role in the formation, maintenance and repair of hoof tissues. Vitamin A,D and E aid in bone and muscle growth, maintenance of healthy epithelial tissue, calcium metabolism control, immune response and activity.  Vitamins C and B-biotin, both water-soluble vitamins, aid in antioxidant activity, lipid metabolism, as well as growth and maintenance of tissues. Biotin aids in the cell-to-cell adhesion in the outer hoof layer.

If you are feeding a commercially produced complete feed, check the guaranteed analysis for these nutrients.  It is also important to check that you are following the feeding directions so the proper levels of nutrients are making it in your horse.  Feed companies formulate the nutrient density and balance based on their feeding directions.  Feeding less than recommended amount means your horse is likely not getting enough of the balanced nutrients he needs.

Hoof supplements are widely available and varied.  If you are feeding a complete feed from a commercial manufacturer that guarentees levels of the nutrients listed above,  you likely do not need to supplement for hoof quality. However, special cases require additional nutrient supplementation.  It is best to work with your vet, farrier and a qualified nutrition consultant to determine the best feed and supplementation program for your horse.

Feeding a horse that has established foot issues such as laminitis takes special care,  as he needs the nutrients in feed but likely not the energy provided.  Excessive levels of starch and sugar per meal increase spikes in glucose and insulin which may have a negative impact on feet.  A low calorie feed or ration balancer  fully fortified with vitamins, minerals and amino acids is your best bet for these special cases. 

Finally, if you have specific questions about your feeding program, check with a qualified nutrition consultant for more information.  A combination of regular hoof care , the right nutrition and proper management for your horse will go a long way in keeping him or her sound for years to come.

Protein in Horse Feed & Hay

Newly born, Ella takes in her worldHorses of all ages require adequate amounts of protein for maintenance, growth, reproduction and work, with growth and reproduction being the most critical time periods.  Proteins are important building blocks for body cells.  Feed intake, growth, physical activity, physical endurance, condition, production of milk and fetal development can all be impaired if protein intake is inadequate.

Most every horse owner can name the protein level of the feed they are currently using.  “A 12% sweet feed” is a common answer when asked that question – but how important is that protein percentage?  While the total protein in the horses’ diet is important, horses actually require essential amino acids, even though crude protein is what is required by law to be listed in a guaranteed analysis.  Many feed manufacturers are moving towards listing the amino acids on the tag, which can help horse owners to see the quality of the protein sources being used.

Beyond the grain portion of the diet, a major factor to watch for regarding protein in an equine diet is the hay source.  After all, hay makes up the majority of the diet, and thus a lot of the protein in the diet comes from the hay. Horse owners need to figure in what their hay sources are providing, and balance it together with their grain source, to determine what their horses are consuming.

Listed below are protein percentages required by the major categories of horses – please note that these are for the TOTAL DIET, not just the grain portion.

  • Foals: 16-18%
  • Weanlings: 14-16%
  • Yearlings: 12-14%
  • Mature horses: 10-12%
  • Lactating mares: 12-14%

In order to figure out the total protein in your horses’ diet, follow this simple calculation:

( (Lbs Hay x Protein in Hay) + (Lbs Grain x Protein in Grain) ) / Total Lbs Fed = Protein in Total Diet

To have an accurate estimate of protein in your hay, it is best to have it tested.  Check with your local extension office or feed store for labs in your area that will do the testing.  Hay protein can vary dramatically from one cutting to the next, and from one field to the next.  Rainfall, stage of growth when harvested, and a variety of other factors can also influence the quality of the hay.  Alfalfa hays are typically considered to be higher protein that timothy or other grass hays, however if alfalfa is harvested late, perhaps due to weather concerns that make it tough to get in the field, it can have lower proteins than some grass hays that are harvested at the proper time.  Thus, it is always a good idea to know the facts behind your hay source rather than “guesstimating”.

A final point that must be made about protein:  Increased protein levels are not generally responsible for a “hot” horse.  Protein is a very inefficient source of energy, and its main use in a mature horse is the re-building of muscle and other body cells after exercise.  Instead, it is the starch and sugars in a horses diet, as well as the calorie intake to calories used (exercise level) ratio, that are primarily responsible for a “hot” horse.  But that’s a topic for another blog post!

Amino Acids in Horse Feeds

Limiting Amino Acids

Most horse owners can quickly tell you the crude protein level in the feed they are giving 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 non-essential.  Essential amino acids must be provided in the diet, as the horse cannot manufacture them on their own in the digestive tract, where the non-essential amino acids can be manufactured.

There is another key thing to know when it comes to amino acids – there are “limiting” amino acids.  This means that if a horse runs out of a “limiting” 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 to provide them also provide the remaining amino acids in sufficient quantities.  It is becoming increasingly common to see these three 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.