http://www.ivis.org Proceeding of the NO Laminitis! Conference 2013 Equine Cushing's and Insulin Resistance Group Inc. (ECIR Group Inc.) Sep. 27-29, 2013 Jacksonville, OR, USA Reprinted in the IVIS website with the permission of the Equine Cushing's and Insulin Resistance Group Inc. (ECIR Group Inc.)
NUTRITION COMPLEXITIES AND MINERAL PROFILES OF HAY Jannalee Smithey, EDO, ESMT Kathleen Gustafson, PhD Good health starts with examining your horse s rations, developing a balanced diet, and replacing what s missing in your horse s hay in the correct amounts and ratios and it shouldn t cost a King s ransom! Eleanor Kellon, VMD Nutrition is the basis of good health in all animal species. Moreover, good dietary management is integral to the prevention and improvement of disease and to self-healing. Forage is the Foundation To create an optimally balanced equine diet we begin by analyzing the main source of food in a horse s diet, which is typically forage. Most horses do well on a good quality grass hay, fed at a rate of 1.5 2% of body weight (15 20 lbs. for a 1000 lb. horse). Unless they are in heavy work, most horses should be able to obtain all of their energy and protein requirements from hay alone. Alfalfa, on the other hand, generally provides more energy, protein, and calcium than that required for mature horses; the exception is 3 rd trimester and lactating broodmares. Through hay testing, we can determine whether the horse will receive adequate levels of nutrients and energy from that hay. It is impossible to tell how good a hay is by just looking at it; despite a sweet smell and plentiful seed heads, a particular hay may lack important major and trace minerals, may be too high or too low in protein, or it may contain high amounts of sugar and starch. Important information can be obtained from the laboratory analysis of our hay sample (e.g., through Equi-Analytical Laboratories in New York 1 ): we will learn the digestible energy (DE), the protein (ideally not >12%), the major and trace mineral levels, and the digestibility (ADF) and palatability (NDF) of the hay tested. For laminitis-prone equines, we will also look at the combined simple sugars (ESC) and starch values, which for most IR horses should not exceed 10%. In short, we want to feed our horses highly nutritious, easily digestible and palatable hay that is moderate in protein and calories and lower in sugar and starch (especially if they are Insulin Resistant or PPID). ECIR Group Inc., 2013 NO Lamintis! Conference, Jacksonville, OR, USA www.ecirhorse.org 1 of 6
With a hay analysis in hand, we can then supplement only what the horse needs, in the correct amounts and ratios, based on the animal s weight and level of work. The ECIR group recommends mineral ratios that take into account the NRC 2 RDA recommendations for equines. We know, for example, that zinc and copper are deficient around the U.S. and, in particular, along the West Coast. We have tested over 400 hays in the Pacific Northwest and every single one of them is not just low in zinc and copper, but is frankly deficient in these two important trace minerals. Zinc and copper are critical, e.g., for ligament and tendon strength, hoof, coat, and skin quality. In addition, when fed in the correct amounts and in the correct ratios to each other, they help to support excretory pathways for iron in iron-overloaded horses (a common occurrence in IR horses). Iron and copper compete for uptake at a cellular level. Even if copper reaches the minimum RDA by feeding supplemented commercial feed, excessive iron (and iron in the supplemented feed) may result in a relative copper deficiency due to competition from iron. For example, in Figure 1., the NRC minimum RDA for a 1000 lb. equine at maintenance is shown in blue. Any value below this would be considered a frank deficiency (see zinc and copper values for hay). Adding a balanced feed will correct the frank deficiencies but also increases values for iron and manganese. In Figure 2, the trace mineral ratios for average hay (250 samples) are shown. Compared to the target mineral ratios, one can easily see the frank and relative deficiencies. Adding a typical commercial feed improves the ratios and may correct the frank deficiencies, but the ratios for iron and copper (Fe:Cu) and manganese to copper (Mn:Cu) remain well above the target. One may argue that this is tolerable, but ECIR Group Inc., 2013 NO Lamintis! Conference, Jacksonville, OR, USA www.ecirhorse.org 2 of 6
considering that the average horse eats the same meal day in and day out for several consecutive months, frank and relative deficiencies will add up. These imbalances are easily corrected by supplementing the appropriate amounts of copper and zinc, which will correct both frank and relative deficiencies. Major minerals should also be corrected, but these tend to be more variable depending on regional differences while copper and zinc deficiency is nearly ubiquitous. Alternative to Hay Analysis and Balancing in Correct Amounts and Ratios The alternative to supplementation without a forage analysis includes such common approaches as the following: 1. Feeding straight grain, e.g., oats, corn, barley, and wheat or rice bran. These are typically high in protein and phosphorus and not necessarily a bad thing if a horse is in heavy work; 2. Feeding grain-based balanced feeds, which are balanced to themselves and may advertise as able to encompass all performance levels and lifespans. With the wide variability in hays across the country, one might question how these products can actually balance hays? A given product may fix a deficiency if fed in sufficient quantities, but at the expense of large amounts fed and the ratios are still not correct; 3. Feeding a commercial balancer, which is designed to balance common feedstuffs based on forages average (legumes vs. grass). Again, given the wide variety in hays between regions, grass species and growing seasons, at best these are approximations; 4. Feeding individual multiple supplements for, e.g., the hoof, coat, metabolic issues, weight-gain issues; 5. Feeding free-choice minerals, which presumes that horses have an innate ability to know which minerals they are deficient in, and to consume only those minerals as needed and in correct amounts. The costs associated with approaches like those listed above can be very high, and may still not provide the horse with adequate amounts of protein, minerals, and digestible energy with which to support a strong immune system. And that is the ultimate goal of feeding a balanced diet, whether or not the horse is IR or PPID. The ECIR Group suggests the analyzing and balancing of one s hay to avoid the absolute and relative deficiencies that are otherwise common place when feeding commercial supplements and untested hay. Feeding a balanced diet is not a cure or fix. It simply addresses the fact that if a horse has a dietary mineral imbalance or frank dietary deficiencies, he may eventually develop problems. Signs include chronic infections, allergies, cracked or shelly hooves or poor hoof quality, brittle or squeaky rough coats, poor manes and tails with burnt red tips. Correct the deficiency and the problems disappear. ECIR Group Inc., 2013 NO Lamintis! Conference, Jacksonville, OR, USA www.ecirhorse.org 3 of 6
The following photos illustrate examples of visible changes that can occur with feeding an optimally balanced diet: ECIR Group Inc., 2013 NO Lamintis! Conference, Jacksonville, OR, USA www.ecirhorse.org 4 of 6
Example of a Balanced Diet Feeding a balanced diet based on hay analysis is not only less costly than using commercial supplements: it s simple and makes good sense. Here is an example for a 1,000 lb. horse at maintenance: Customized minerals to match tested hay (or a regional mix, if testing hay problematic); 2-4 oz. of ground flax (the omega 3:6 ratio matches that of fresh grass); 2-6 oz. of plain, white, iodized salt (depending on level of work and weather; pink/brown salt contains dirt, which contains iron); 2,000 IUs of natural vitamin E in gel caps (containing oil for absorption); A carrier in which to mix the above, e.g., tested grass hay pellets/cubes (Ontario Dehy Timothy Balance cubes) or rinsed/soaked/rinsed beet pulp. ECIR Group Inc., 2013 NO Lamintis! Conference, Jacksonville, OR, USA www.ecirhorse.org 5 of 6
Feed the Work! In thinking about how much to feed our horses, we need to consider their level of activity. A pasture pet will obviously not require what a hunter-jumper needs, working five days a week. Racehorses are in quite another category. The 2007 NRC has recommended categories of work defined as follows 3. They are not set in stone, but are estimates to guide us as we calculate our horses rations: Light = Mean Heart Rate: 80 beats/minute. Description: 1 to 3 hours per week; 40% walk, 50% trot, 10% canter. Moderate = Mean Heart Rate: 90 beats/minute. Description: 3 to 5 hours per week; 30% walk, 50% trot, 10% canter, 5% low jumping, cutting or other skill work. Heavy = Mean Heart Rate: 110 beats/minute Description: 4 to 5 hours per week; 20% walk, 50% trot, 15% canter, 15% gallop, jumping or other skill work. Very Heavy = Mean Heart Rate: 110 to 150 beats per minute. Description: From 1 hour per week very high speed work to 6 to 12 hours per week slow work. This category includes QH, Tb and Standardbred racing, Endurance, Upper Level 3-day eventing. Summary While supplementing based on forage analysis is outside of the norm for most horse owners, the payoff with respect to performance, health and cost is worth the effort. While the value of a balanced commercial feed or supplement is appreciated and considered a sign of excellence, few horse owners appreciate the lack of balance in 20 lbs. of forage vs. a little bit of feed and a supplement. Commercial feeds may correct frank deficiencies but only if fed at the recommended amounts suggested by the manufacturer. Most horse owners restrict that amount to a handful because their horse will gain too much weight, becomes hot or in an effort to control cost all of which are counterproductive. Most horses at maintenance do not require large amounts of grain-based feeds. Forage analysis and targeted mineral balancing is more sensible and cost-effective. 1 Equi-Analytical Laboratories, 730 Warren Road, Ithaca, New York 14850; Ph: 1-877-819-4110. Email: service@equi-analytical.com 2 NRC. 2007. The Nutrient Requirements of Horses, 6th revised edition. National Academy Press, Washington, DC. 3 Ibid. ECIR Group Inc., 2013 NO Lamintis! Conference, Jacksonville, OR, USA www.ecirhorse.org 6 of 6