Standing in line at my local Co-op the other day, I heard the question of all questions from an overwhelmed soul in front of me. “There are so many options… Which is the best feed for my horse?”
While seemingly a simple question, there are hundreds of horse feed brands, each one having numerous feed blend options, bringing many horse owners to a ‘deer in the headlights’ reaction. Fortunately, when we understand a horse’s nutritional demands, what a good quality horse feed looks like, and what feed type the horse needs to satisfy his nutrient requirements, the question changes shape. Here is a overview of a horse’s required nutrients and a few basic guidelines we can use to sift through to “the best feed” for the horse.
Horse’s Required Nutrients
Every horse has the same foundational nutrient requirements. In relative balance, these six pieces should complete the puzzle of what makes up the horse’s ideal diet. Here is a brief overview of the puzzle pieces. **For a constant reference and in depth breakdown, I highly recommend National Research Council’s “Nutrient Requirements of Horses”. **
Water is the most essential and overlooked nutrient in a horse’s diet. Horses need enough water consistently for proper systemic and cellular function. Where “enough” water is relative depending on the horse’s mass, environment, physical demands, and other factors, horses typically need between 10-15 gallons of water each day.
Fiber is a structural carbohydrate and the most important energy source in a horse’s diet. Where starch (nonstructural carbohydrate) requires enzymatic digestion to offer nutritional value to the horse, fiber requires microbial digestion. Horses consume fiber rich forage in bulk compared to other feedstuffs, giving it powerful influence in not only the nutritional value of the horse’s diet, but also the overall mechanical function, pH balance, and efficacy of the GI tract.
Fiber digestion occurs primarily in the horse’s cecum, the first digestive organ making up the hindgut. Billions of microbes reside here, fermenting and feeding on these structural carbohydrates. The microbes then excrete VFAs (volatile fatty acids) that the horse utilizes for around 70% of his dietary energy.
Starch is a nonstructural carbohydrate (NSC) that provides the horse with energy through enzymatic digestion, primarily in the small intestine. Digestive enzymes break the NSCs down to their simplest form of glucose, then reassemble them for immediate energy use or storage as glycogen in the muscles and liver.
Because glycogen is an immediately available energy source, and the most efficient way to generate muscle contractions, starch consumption in the athletic horse is valuable. At the same time, a diet overwhelmed with starch will contribute to ‘hotness’ in a horse’s behavior and have negative effects on microbial population in the hindgut.
Fat is the most calorically dense nutrient a horse can consume, with 2.25 times as much energy as starch. A horse’s digestive tract has a generous capacity to increased fat in the diet. On a forage only diet, dietary fat content will be around 1-4%. Given time to adjust, horses can tolerate a diet of up to 20% fat. However, fat is less versatile than starch due to its need for aerobic use (oxygen present), so a balance between fiber, fat, and starch, makes for optimal calorie sourcing in the athletic horse.
Dietary protein is digested primarily in the small intestine, broken down into individual amino acids, and assembled into biological proteins once absorbed through the blood stream.
Where dietary protein requirements range from about 8-10% in the mature idle horse, to about 15% in the growing/lactating horse, it’s easy to meet crude protein requirements with quality hay and grain mix. However, it will be important to ensure that the amino acid profile in the horse’s dietary protein is broad and balanced in order for absorbed amino acids to reassemble sufficiently into biological proteins.
Vitamins & Minerals
Vitamins are organic components necessary for an animal’s metabolic process. They act as coenzymes and precursors to coenzymes, essentially assisting in enzymatic function. Vitamins can be broken into two categories. Fat soluble vitamins (A, D, E, & K) can be stored in fat within the body. While the problem with these vitamins is typically deficiency, they can be toxic if concentrated in the body at excessive levels. Water soluble vitamins (B and C complex) cannot be stored in the body and are excreted in urine.
Minerals are inorganic substances that also support metabolic process. Minerals are categorized into macro and trace. Macro minerals, such as calcium, phosphorous, potassium, magnesium, sodium, chloride, and sulfur, are needed in larger quantities by the body. Trace minerals like copper, zinc, manganese, selenium, cobalt, and iron, are required by the body in much smaller quantities.
Horses are subject to vitamin and mineral deficiency in a forage only diet, particularly a diet made up primarily of dried forage. Similarly, an unbalanced diet or unsuitable concentrate ration can also lead a horse to imbalances in vitamins, minerals, and supplemental amino acids, a subset commonly referred to in the feed industry as “micros”.
4 Steps to choosing the ‘best’ feed for the horse
Today, nutrition is at the forefront of scientific development in the horse industry. With companies working hard to develop the most most desirable products for the athletic horse, we have the privilege of choosing the best of the best. When it comes to determining the quality and suitability of a horse feed, we can start with four pointed questions.
1) Is the feed milled in an ionophore free facility?
Ionophores are medicated feed additives beneficial to the feed efficacy in ruminants (cows, goats, and sheep). Unfortunately, even a small dose of ionophore contamination is toxic and often lethal to a horse. While feed mills will have procedures in place to prevent contamination between medicated feed batches and equine feed batches, accidents can happen. With that, there are plenty of options in today’s horse feed industry that we as horse owners can simply choose to purchase feed from companies that do not mill medicated products and horse feed at the same facilities.
2) Are the ingredients in the feed consistent?
If we look at a feed tag, we see two segments. The first segment will be a list of crude percentages. This typically means that 12% crude fat will give yield 12% crude fat per lb of feed. Convert the percentage, and we have about 54g fat per lb of feed.
The ingredients used to make up the crude fat content are not held to the same calculated value. The ingredients on a feed tag will be located in a list below the crude percentages. That 54g of fat will be much more useful to the horse if it comes from bioavailable soy oil than if it were to come from virtually indigestible animal fat.
Moreover, the ingredient consistency determines the horse’s ability to digest the nutrients. Horse feed can be classified as a least cost formula, or a fixed formula. While the former is becoming less common, we will periodically still see feeds that look like the top label, with unspecified energy and protein sources. This allows companies to interchange ingredients used to fill the crude percentages of starch, fiber, fat, and protein to manufacture at a lower cost. Unfortunately, a horse’s digestive enzymes and microbial population are fine tuned and sensitive, and will be negatively impacted with an influx of unfamiliar digesta. In short, steer clear of least cost formulas due to the volatility of the feed from batch to batch.
Instead, there are plenty of horse feeds made in fixed formulas (see label to the right of the cubes). Where ingredients are consistent, we can easily judge whether or not we want our horses eating what the feed contains.
3) Is the micronutrient profile sufficient?
After establishing that a feed is milled in a medication free facility, and that it is formulated with fixed, digestible energy sources, it’s time to pick a brand. Choosing the most suitable brand for the well horse may come down to that brand’s ‘secret sauce’, or the micronutrient profile.
The vitamins, minerals, and amino acids added into a feed will vary in presence, quality, and density. When looking at a feed tag, we want to see plentiful vitamin and mineral supplementation. Chelated minerals also add to the feed’s value, as these minerals are attached amino acids and well absorbed by the horse. A broad variety of supplemental amino acids, such as lysine, threonine, methionine, arginine, and cysteine also increase the horse’s ability to utilize dietary protein. Lastly, feed companies now a days also add prebiotics, probiotics, and support structures for biological enzymes into feed blends. This is valuable to increasing the efficacy of GI function.
4) Can you feed per the instructions on the bag?
Once we’ve established which feed brand to pull from, we must ensure to choose an appropriate feed blend within the brand, or our effort and financial investment will be wasted. How can we pick the right feed blend for the horse?
Read the feeding instructions. If the horse’s energy (caloric) needs are met and not exceeded within the recommended feeding rate perimeters, the feed is suitable. otherwise, pick a different feed blend.
For example, The Well Horse’s Dazzle Mi Amigo is a 23 year old paint mare. She is powered by Tribute Equine Nutrition products. If I were to feed her Kalm Ultra, to reap the benefits of this feed she would need to eat minimally 6 lbs of Kalm Ultra daily. She would be obese in this scenario. The alternative would be to feed her 2 lbs of Kalm Ultra daily- no obesity. The problem here would be that micronutrients are included in the feed at an optimal density for a daily 6 lb feeding rate. By feeding 2 lb, Dazzle gets 1/3 of the micronutrients that the feed is designed to give her. Instead, Dazzle eats 2 lbs Essential K daily. Essential K is a less calorically dense feed designed for a 1-2 lb daily feeding rate. Same company, same nutritional benefits, more suitable blend for the horse.