I routinely look at hay analysis sent by customers needing an interpretation of the data. We have arrived at a point in the care of our horses where a hay analysis is imperative — not only for the metabolic horses, but for all horses — because there has been a trend in hay nutritional quality the last few years that reflects weather conditions and farming practices.
Protein levels have dropped in hays such as timothy and orchard grass. I have recently seen a mixed orchard/timothy hay analysis showing protein at 6% and a whopping 17% NSC (non-structural carbohydrates). Ideally we’d like to see the opposite: 17% protein and 6% NSC. Performance horses, young growing horses, pregnant mares, older horses, and horses recovering from injury need higher protein values.
NDF and ADF
In a hay analysis, “ADF” is a measure of cellulose and lignin, the least digestible plant components, while “NDF” is a measure of all the fiber in the plant: hemicellulose, cellulose, and lignin. The higher the percentage of ADF and NDF, the more lignin the hay contains.
ADF values increase as hay maturity increases, and these higher values mean lower digestibility. Hays that are too high in indigestible fibers can increase the risk of GI tract disturbances, particularly in the hindgut. Lignin has very low digestibility in horses. I commonly see hay analysis with NDF at 65% or higher.
Dr. Kathleen Crandell, an equine nutritionist with Virginia Tech’s Middleburg Agricultural Research and Extension Center, estimates that high-quality forages tend to have ADF values of 25-35% and NDF at 35-55%. Lower-quality hays will have an ADF of 35-45% and an NDF of 55-70%. She cautions against feeding hay that is over 65% NDF because it increases the risk of impaction.
Good-quality hay will have more leaf than stem. Very leafy hay will be lower in ADF and NDF and will be more digestible.
Vitamins and minerals
Vitamin A (in the form of beta carotene) and vitamin E, which fresh forage provides, lose potency during hay storage. The longer the hay is stored, the more these fat-soluble vitamins degrade. We are seeing more hay now, tested after bailing, with low vitamin E levels. It’s also increasingly common to see low levels of specific minerals: magnesium, zinc, copper, selenium, and sodium.
Soil health and glyphosate
Weather is something a farmer can’t control, but how the soil is nurtured is revealing more and more about the limitations and problems with industrial farming and, ultimately, the quality of hay.
Among the critical elements of the soil matrix are microbes and fungi. They break down decaying plant matter to create a rich biomass, and help convert inorganic forms of minerals (carbonates and oxides) into organic forms the young growing plants need.
Long-term chemical fertilizer applications on fields significantly affect soil microbial communities by reducing their population, lowering carbon content and leading to acidification of soils.
Organic fertilizers such as neem cake and manure support the microbial communities in the soil, as well as a higher soil pH and an increase in the soil’s carbon and nitrogen levels. Because the microbes are so important for converting earth minerals to organic forms the plants can use, higher mineral content is often found in hay that has been grown without chemical fertilizers such as nitrogen.
Farmers are being encouraged by Monsanto to use the herbicide glyphosate (Roundup) as a desiccant, to be applied to the hay after cutting. A 2010 study published in Plant and Soil (volume 328, issue 1-2, pp57-69) highlighted a significant decrease in macro- and micronutrients in leaf tissues of soybean plants after glyphosate use.
According to Dr. Don Huber (Plant Pathology, Purdue University), glyphosate “gives the plant AIDS.” It kills weeds by turning off key enzymes that produce defense mechanisms for plants and targets the immune systems by binding up magnesium, copper, and zinc from the plant. Those three minerals are often deficient in many hays.
Some farmers use glyphosate to kill weeds in their pastures because they say horse owners don’t want to see weeds in their hay bales. Of course we horse owners don’t want toxic weeds in our hay, but if glyphosate reduces the mineral content of our hay, maybe a few friendly weeds should not be our biggest concern.
Balancing protein deficiencies in hay
To increase protein when feeding low-protein hay, add alfalfa hay (26% protein on average) or alfalfa pellets or cubes (15-17% protein) Alfalfa is a complete protein for horses, providing all the essential amino acids.
Coconut meal (Cool Stance) provides 20% protein and Renew Gold (a blend of coconut meal and rice bran) provides 15% protein. Note that Renew Gold would not be the best choice for metabolic horses due to the high NSC content of rice bran.
There are many protein supplements on the market that provide high levels of protein — 30% or more. Excess protein can be used for energy by the horse, which is often why alfalfa hay, at 26% protein, can be too much for some horses and makes them overly energetic. Also check the amount of sugar and starch in some of these protein supplements, because they can be quite high.
Many common equine protein supplements consist of “whey protein isolate” or “whey protein concentrate”, which are denatured during the high-heat processing and acid flushes. This strips the whey of other beneficial factors including nutrients, peptides, and immune factors.
Soy isolate is also a common ingredient in protein formulas and muscle-building formulas. Soy is genetically modified, the crop commonly sprayed with glyphosate. Soy has endocrine-disrupting compounds. Look for protein and muscle-building formulas with un-denatured whey protein and no soy.
BioStar’s un-denatured, soy-free protein supplements include:
Vitamins and minerals
Even if you are feeding a complete feed, it is formulated according to typical hay nutritional analysis of many years ago. It is imperative to add a multivitamin/mineral if your hay tests low on critical nutrients: vitamin E, beta carotene (vitamin A), zinc, copper, selenium, magnesium.
If both your forage and your hay are low in vitamin E, you may need to add additional vitamin E supplementation even when feeding a multivitamin/mineral.
Get a CBC
It is very important to pull a complete CBC blood panel every year or twice a year on your horse, particularly a performance horse. I do a CBC on the retired horses once a year, just to make sure everything is in balance. If a certain mineral such as magnesium or zinc or copper is low, then I know to supplement that or add foods that are high in that particular mineral.
Protection from glyphosate for the gut
Studies in France and the UK have shown that glyphosate can degrade the tight junction barrier in the GI tract. The tight junctions form a nearly impermeable membrane, allowing only what is desirable into the cell. Glyphosate weakens the tight junctions that protect the horse from environmental toxins and can lead to intestinal permeability—what we often call leaky gut. Weakened tight junctions trigger an inflammatory process by triggering immune-activating lymphocytes and T-cells.
Remember, hay is not the only food sprayed with Roundup as a dessicant; so are soy, wheat, peas, sunflowers, sugar beets, pastures, and even apples. Still, the number one sprayed crop is soy with wheat coming in second. Organic farming does not allow Roundup use.
Studies have shown that fulvic and humic acids (components of peat, lignite, and shilajit) easily bind toxic and other harmful substances including herbicides, pesticides, heavy metals, mycotoxins, and organic pollutants. Fulvic and humic acids can help close the tight junctions of the gut. Adding shilajit or a lignite extract can be beneficial for horses exposed to glyphosate in hay and feed.
Points to remember:
- Getting a hay analysis is important to ensure your horses are getting the nutrients and protein and digestible fiber they need.
- Getting a CBC done at least once a year is important for maintaining a baseline of health, and for knowing where nutritional imbalances may be occurring before they become a problem.