By Dan Houdeshell
© 2007 – Sierra Ranch Supply, Inc. – All rights reserved.
It’s kind of sad that we have finally come around to greatly reducing the sugar intake of our kids in spite of the complaints and withdrawal symptoms, yet some continue to baby, pamper, bribe and cajole their horses with tons of the stuff. Then they act surprised when the poor horse ends up with health problems such as the “ailment de jour”, insulin resistance. We will be covering Equine Metabolic Syndrome (EMS) in a subsequent article but for now let’s look at how much sugar we feed our horses.
EMS has created a whole new market niche of “low carb” feeds for horses. The horses that are subjected to this kind of feeding are forced to metabolize fat and protein to fill energy needs. On the human side some would call this the “Atkins Diet”. Is it good or bad? The jury is still out on that one. One thing is for sure, fat is a slow burn source of energy and requires a lot from the liver to be properly digested and used as energy. When the body is forced to convert protein into energy a great number of toxins are released into the body placing a lot of stress on the kidneys. This actually causes its own string of problems.
All of that aside, if you want to control how much sugar your horse eats, you had better start with his hay. That's right, hay contains sugar and starch levels that need to be taken into consideration when calculating daily ‘sugar’ intake.
All hay is not created equal.
One of the biggest misconceptions is that alfalfa hay is bad for horses. While it does have mineral content issues that need to be addressed and properly supplemented, alfalfa has less sugar content than most grass and small grain hay. It is important to know what the tested nutrient values of your hay are when calculating a properly balanced ration for your horse. Testing may not be practical for some horse owners due to the fact that they are buying hay in small quantities and the hay dealer receives hay from many different producers.
If this is your situation what can you do? The following information will help you to see and compare different types and forms of forage so that you can make an informed decision.
The Market
Hay growers are focused on supplying the largest market for their crops, the dairy industry. From January 1st to October 6th of 2006 dairy producers in California had purchased 1,700,000 tons of alfalfa at between $178.00 and 198.00 per ton. The dairy producers want hay with a high Relative Feed Value (RFV). This value is shown on forage tests that are performed correctly. What does it mean?
“Relative feed value (RFV) is a term that has been used in the marketing of hays. It can be calculated for pure grass and legume or mixed hays. To calculate this value it is necessary to have a forage analysis for acid detergent fiber (ADF) and neutral detergent fiber (NDF). It does not consider protein but higher RFV values would usually be associated with higher protein. The ADF analysis is used to predict the digestible dry matter = (88.9 - (.779 * % ADF)) and NDF predicts dry matter intake = (120/% NDF). RFV is calculated by multiplying digestible dry matter by dry matter intake and then dividing by 1.29. For an alfalfa hay containing 30% ADF and 40% NDF the RFV = (65.5 * 3)/1.29 = 152. Grasses typically have higher ADF and NDF concentrations and consequently have lower RFV. For instance a grass or mixed hay having 35% ADF and 50% NDF would have an RFV = (61.6 * 2.4)/1.29 = 115. What this calculation does not account for is ADF and NDF digestibility. Grasses typically have fiber digestibility's greater than legumes because legumes have more lignin associated with the fiber. Legumes make up for this by having more cell contents that are highly digestible thus elevating energy concentrations to higher levels than in grasses. When using RFV it is best to compare hays that are within a similar classification such as alfalfa, grass, or mixed. Commercial labs typically have the ability to provide RFV for hay crop forages. If you are interested, contact your local Extension Office for a list of commercial labs.”2
Now if all of these acronyms have your head spinning here is a crash course in livestock nutrition terminology. When looking at feed analysis you will see the following:
CP = Crude Protein, nitrogen content that can be converted into amino acids.
TDN = Total Digestible Nutrients, the energy in the feed.
ADF = Acid Detergent Fiber, fiber and lignin that is difficult to digest.
NDF = Neutral Detergent Fiber, fiber that is easily digested.
NSC = Non-Structural Carbohydrates, carb’s from non-fiber parts of the plant.
But, what about the sugars?
Thankfully, since most hay is sold on the basis of RFV and must be tested, there is a vast amount of test information compiled each year that we can draw from. Two laboratories that offer such information are Dairy One™ and Equi-Analytical Laboratories. We have compiled test results from these two labs to produce the charts below. In these charts you will find the “average” levels of sugar, NSC (non-structural carbohydrate) and the low and high range of each. We have to be careful not to take the average and be satisfied that we are using the correct number. Here’s an example:
If you have two bowls of water, one with ice water and the other with boiling water, and you put one hand in each bowl; on the average you should be comfortable. In reality you will not be comfortable and in fact you will be hurting yourself. It’s much the same when using average forage test numbers to formulate your horse’s ration and supplement it correctly.
Table 1. Sugar Levels in Different Types of Hay3,4
Hay Type Samples Tested Average Low High
Legume Hay 48,574 9.014 7.255 10.777
Alfalfa Cubes 223 7.781 5.958 9.595
Alfalfa Pellets 83 7.124 5.475 8.772
Barley Hay 82 14.028 8.201 19.854
Bermuda Grass Hay 3,518 7.321 5.560 9.083
Grass Hay 16,581 10.783 6.373 15.192
Oat Hay 2,957 17.950 9.758 26.133
Triticale Hay 203 21.382 14.410 28.354
Wheat Hay 485 13.358 6.978 19.739
And what about the NSC?
“Horses vary in their reaction to NSC, and so there are no absolute numbers that can be considered safe for every laminitic or insulin resistant horse. As per the Dairy One database grass hay averages about 13% NSC. It's just common sense that we should target below average levels for horses with glucose intolerance. After consideration of follow up testing of glucose and insulin levels on more sensitive animals, I feel safer with 10% or less NSC for grass hays is a good target for a horse in trouble. Any horse that has acute laminitis or very high insulin levels should certainly be at, or below these levels. Of course the same horse may do fine on 12-14% NSC hay if regularly exercised and kept at a fairly high level of fitness. This is only one of many factors in managing insulin resistant, laminitic animals, which includes exercise, prevention of mineral deficiency and appropriate hoof care, but I feel the most important one. Mine are not the only horses that have had major improvement in long-term laminitis by minimizing NSC in the hay.” 5
The key statement in the excerpt above is “horses vary in their reaction”. This is because they are individuals the same as you and I are. You have to know your horse and decide what is best for him in your situation. Understanding what will be best for your horse requires that you educate yourself about the options available and that requires reading, study and attending some seminars on the subjects that you need help with. Knowledge is power, is as true as it has ever been. Since we live in the information age and sources such as the internet are flooded with it, help in disseminating this information is valuable. That is where seminars come in. The time and cost invested in your horse will pay you back many fold.
Table 2. NSC Levels in Different Types of Hay3,4
Hay Type Samples Tested Average Low High
Legume Hay 41,162 10.942 8.779 13.105
Alfalfa Cubes 229 9.749 7.245 12.252
Alfalfa Pellets 83 9.767 6.869 12.655
Barley Hay 63 19.462 12.778 26.145
Bermuda Grass Hay 3,449 12.808 8.744 16.871
Grass Hay 16,185 12.924 8.068 17.779
Oat Hay 2,904 22.258 15.077 29.866
Triticale Hay 202 23.906 17.052 30.760
Wheat Hay 484 17.315 10.070 24.633
Using the chart above we can choose from among the types of hay in your area to properly suit your horse’s needs. Since the EMS horse will benefit from feeding a lower NSC diet, we need to find the best forage to accomplish this. If you are not able to test the hay that you buy, you will need to choose the hay with the narrowest margin between high and low levels. We also need to remember that the more samples that are tested, the more accurate the test results are in showing trends for that type of forage.
From the information that we have considered so far, if we are going to target 10% NSC with a ceiling of 14% our choices have been greatly reduced. Using the chart above we can plainly see that:
1. Barley, Oat, Triticale and Wheat hay are out.
2. ‘Grass’ and Bermuda Grass hay are marginal.
3. Alfalfa hay, cubes and pellets are well within the safe range.
My purpose in writing this is not to promote the feeding of alfalfa as I have no financial interest in that at all. My only financial interest is in the amount that I have to pay for it the same as many of you. It is simply to show that even well intentioned counselors who tell you that you need to “get your horses off of alfalfa” to correct any metabolic disorder are sadly misinformed. You have the flexibility of feeding the type of hay available in your area without compromising your horse’s wellness and ability to thrive.
We have also learned from this discussion that regular exercise, good hoof care and proper mineral supplementation are key components to helping your horse thrive. If you have questions please do not hesitate to call us at:
800-580-6632 or email to srs@sierragoldhorses.com
References:
1. Seed Today: California Hay and Seed Update – October 18, 2006
2. Charles C. Stallings. Virginia State University, Virginia Cooperative Extension – October 2004
3. Dairy One™ Laboratories Forage Composition.
4. Equi-Analytical Laboratories Common Feed Profiles.
5. Rocky Mountain Research & Consulting, Inc – 2005
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