Wound Care in Winter

If there’s one good thing about winter, it’s that you don’t have to deal with insects bothering wounds. This does eliminate one source of wound infections. However, the benefits stop there.

The cold, dry air in winter leads to a major cause of delayed healing, dehydration of exposed tissue. A moist environment is important for cells to migrate across the wound and for white cells to do their work cleaning up the wound. Suturing wounds that warrant it, and keeping other wounds covered with a protective ointment will guard against dehydration.


Choose a topical treatment which will prevent the wound from drying

The cold itself can also be a problem because blood flow is decreased to the skin in cold weather. Inflammation helps counteract it in the early stages of healing but once that calms down, in 3 to 5 days, blood flow is not as good as in warmer weather. This slows healing by inhibiting cell migration and can also mean the difference between death or survival of areas of skin that have a damaged blood supply from the injury.

Because of the detrimental effects of cold, dry weather, wounds need more protection. Even small skin breaks in areas with a lot of movement, like the heels and pasterns, can quickly become painfully deep cracks.  Keep an eye out for wounds on your small animals too and regularly check their paws for cracking.

Good choices for holding in moisture on wounds are ointments and salves without a water base. Look for petrolatum, beeswax and oils.  Help with temporary irritation and discomfort comes from ingredients like Arnica, Chamomile,  Comfrey, Calendula, Witch Hazel, Plantain, White Willow Bark, Golden Seal and Vitamin E.  Natural ingredients with antiseptic advantages include Tea Tree Oil, Oregon Grape, Echinacea, Gentian, Sodium Copper Chlorophyllin and all essential oils.  Protect delicate new skin with the antioxidant benefits of  Chaparral, Burdock and St. John’s Wort.

For wounds on the lower legs, apply a generous amount of salve after cleaning gently with warm water then cover with several layers of gauze (never use cotton on open wounds) and a standing leg wrap over that. To avoid having your gauze slide down inside the wrap, use a dab of your wound dressing to hold the gauze layers together and also to hold it where you want it inside your leg cotton wrap, then apply the wrap as usual. Check and rebandage once a day for the first few days, or until drainage has stopped.

Tip: For ease of use and your horse’s comfort, do not store wound products in the cold – including in tack trunks.  Keep them in a heated room and when working on your horse place them inside your clothes as close to your body as possible until you are ready to use them.

Winter weather is no friend to skin.  Fight compromised healing by preventing tissue dehydration with oil/wax based salves and ointments and taking advantage of many helpful actions of herbal ingredients.

Eleanor Kellon, VMD

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Balance is Everything

Homeostasis is a continuously occurring dynamic process that seeks to maintain balance between body processes and a stable internal environment. The Chinese describe it as a balance between Yin and Yang.


                 There’s a lot going on beneath the surface in this tranquil setting.

A healthy horse at rest may seem as tranquil as a quiet bay on a sunny summer day but the truth is even a well horse is more like the ocean side, with waves coming in and out, high and low tide. When your horse has a serious injury or illness, it’s tsunami or hurricane time!

A (relatively) simple example would be temperature regulation in different weather situations. Under neutral conditions, the blood vessels to the skin are neither overly constricted nor dilated. When very hot, blood flow to the surface blood vessels increases, which also triggers increased sweating  and if more cooling is needed breathing increases to allow for heat loss in expired air. When very cold, balance of blood flow to the skin and sweating swing to the other side of baseline by decreasing. When the temperature stress resolves, the blood vessels return to their normal neutral state, sweating abates, breathing is normal.

Maintaining temperature is actually much more complicated, involving the brain, autonomic nervous system and mediators such as dopamine and epinephrine. Even the process of creating sweat is wondrously complicated.  When you get into the realms of internal fluid balance, pH regulation, urine production, the immune system, detoxification reactions, etc. the complexity mounts.

Cytokines are small proteins released by cells which they use to communicate with each other. The surface of a cell is covered with receptors which will recognize specific types of cytokines (or hormones, or amino acids, etc.). Over 45,000 cytokines have been identified since they were first described in the 1960s and researchers agree they are just beginning to uncover them all. They are particularly active in the immune system. For every  cellular activity influenced by cytokines there will be some that trigger and others which suppress. Balance.

Underneath the healthy horse’s tranquil exterior billions of cells are busily doing their jobs. Functions are being turned on and off as needed to keep the basics of body temperature, electrolyte levels, blood volume, and a host of other things stable within a fairly narrow range. When this balance is threatened by something like an infection, activity ramps up significantly until the challenge is successfully eliminated, at which point homeostasis is achieved again.

Many things we do to care for our horses, such as providing shelter, vaccinations, dewormings, help them to maintain homeostasis but the most important of all is nutrition. They can survive all sorts of nutritional shortfalls but surviving is not thriving. They need adequate quality protein to build cells, make cytokines, hormones and antibodies. Structurally important minerals of calcium, phosphorus and magnesium also play critical roles in muscle activity, nerve transmission and energy generation. Antioxidant vitamins and minerals protect the cells from damaging free radicals being generated all the time from immune system activity and the burning of fuels. Proper nutrition makes homeostasis possible and that balance is the definition of health.

Eleanor Kellon, VMD


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Fine Tuning Winter Feeding

Plenty is written every year about the basics of winter feeding, including:

  • Lots of hay/fiber
  • Increase calories to compensate for energy lost staying warm
  • Feed salt
  • Constant water at a comfortable temperature for drinking

These things are critically important for all horses, to help prevent weight loss and impaction. However, it doesn’t stop there for special needs horses.

Credit: Thinkstock

Low moisture winter feedstuffs are also a risk factor for choke in older horses in general and especially if their chewing efficiency is poor.  Soaking meals helps but isn’t always enough when the horse does not chew well.   The saliva produced during normal chewing is rich in mucin which lubricates the food bolus on its way through the esophagus.

Adding psyllium to wet meals can help replace the lubricating effect of mucin. It has a very high soluble fiber content which adds a slippery/slimy texture to the food. That’s not particularly appealing to us but horses eat it right down.  Regular use of psyllium also has a prebiotic effect in the large intestine.

Speaking of the large intestine, for these high forage diets to do any good they have to be efficiently fermented. That takes a vibrant thriving population of organisms.  There are many horses, older horses in particular but younger ones as well, that do not handle high fiber hays well. A common sign of this is fluid leaking around formed manure.  You may also see some bloating/distention and difficulty holding weight even with generous feeding.

Prebiotic easily digestible fiber, like the psyllium above, combined with high potency gut support can turn this around. Digestive enzymes (lipase, protease, amylase) help insure that protein, fat and starch are digested and absorbed in the small intestine so they do not reach the large intestine where they can be disruptive to fermentation.  High concentrations of active yeast and probiotic organisms as well as fermentation products produce a favorable environment for effective fiber fermentation in the large intestine.

One of the most difficult situations to handle is the horse that still cannot maintain a healthy weight despite high rates of feeding and digestive tract support. The horse does not have to be grossly fat to benefit from the heat conserving effects of a normal fat layer. Enough fat to cover the ribs and keep the bones from obviously protruding will do it.

If your horse cannot maintain that much weight the cold will be much harder on him. Grains are the next step up in terms of calorie density but some horses do not tolerate them well for metabolic reasons while others pass too much undigested into the large intestine where it causes more harm than good.

Supplemental fat can be the solution.  Caloric density is very high and converting dietary fat to body fat is done efficiently.  Coconut oil is particularly easy to metabolize and is by far the most appetizing. Even cats can’t resist it!  Incorporating flax oil or full fat flax or chia seeds also replaces key essential omega fatty acids lost when grass is cured to make hay. New choices, like high oleic sunflower oil, are both metabolically healthful and compatible with maintaining a good omega fatty acid profile in the diet.

Eleanor Kellon, VMD

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Your Horse Needs Inflammation

Inflammation is always talked about as something you need to avoid or control.  There is a staggering number of medications, supplements and therapy devices that target inflammation. However, inflammation is an essential part of how your horse’s body functions.

Image result for horse thermography

                  Thermography is used to detect areas of potential inflammation.

Most people define inflammation as pain, swelling and heat but these are the outwardly detectable consequences of inflammation, not inflammation itself. Inflammation is the immune system’s response to infection, injury, foreign/irritating substances and abnormal or dead cells. Even cellular stress that does not cause serious damage will trigger an inflammatory response.

Inflammation can be localized, as in an injury or abscess, or systemic like a viral infection. Inflammation itself triggers release of anti-inflammatory countermeasures and as the cause of the inflammation comes under control, e.g. organisms neutralized or dead tissue cleaned up by scavenger white cells, these anti-inflammatory forces become dominant and the inflammation resolves. Inflammation is also necessary for the release of various growth factors which take over the job of repairing tissues. Without inflammation, these healing messengers would not be released.

Inflammation has a role to play in responses to things other than trauma or infection. When the horse is in training there is ongoing stress to the muscles and joints which results in microscopic damage that is so slight you can’t tell anything is going on. These stressors  trigger the release of inflammatory chemicals and in turn growth factors. The ultimate result is bigger and/or stronger muscles and bones.

An important thing to remember about inflammation is that it has to be turned on by some need. There is always a trigger. On a day to day basis inflammation is involved in normal cellular housekeeping like removing cells as they die, repairing minor damage to the intestinal lining or neutralizing irritants in inhaled air. When the job is accomplished, inflammation is turned off again.

What about inflammation causing disease? We hear a lot about that these days in reference to human health conditions. However, even when increased inflammatory activity is clearly associated with something it is never the cause. The real cause is whatever is turning on the inflammatory response.

There is also a lot of talk about diet causing – or curing – inflammation. Despite a lot of theory and hype there is no evidence that things like high omega-6 fatty acid intake can actually cause inflammation. In fact, there is mounting recent evidence that it doesn’t.  On the flip side, antiiinflammatory dietary elements like omega-3 fatty acids, vitamin E and trace minerals don’t cure inflammation either but they will provide the body with the raw materials it needs to mount its own normal antiinflammatory activity if any of these nutrients are deficient.

In summary, while inflammation can cause your horse pain and certainly signals there is an issue, it is not the cause of the problem.  Once the trigger of the inflammation is removed the inflammation will resolve itself within 72 hours if your horse has a sound diet. The horse then enters a stage of healing that wouldn’t be possible without the inflammatory response.

Eleanor Kellon, VMD


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Cold-Induced Laminitis

It happens every winter. A horse that may not even have a prior history of laminitis is found to be very lame and reluctant to move.  It’s more than the typical hesitation horses show on hard, frozen ground. Looks like laminitis but the feet aren’t hot. What’s going on?

Cold-induced hoof pain strikes horses with insulin resistance. IR is a well described risk factor for laminitis and even when the horse is not glaringly lame it is causing damage to the laminae. We haven’t uncovered all the mechanisms behind laminar damage from high insulin levels but one known factor is elevated levels of endothelin-1.

Endothelin-1 is a peptide (small protein) produced by the cells lining the interior of blood vessels. It is the most potent vasoconstrictor known and is normally balanced by production of the vasodilating chemical nitric oxide. Cold-induced reduction in blood supply to the hoof when superimposed on the pre-existing high endothelin-1 activity may explain why some IR horses develop hoof pain in cold weather but normal horses do not.

Cold stress may also cause insulin to rise.  Insulin resistance is part of the metabolic adaptation to cold weather in several species.  Researchers have also noted insulin levels become erratic in horses in cooler weather.

Laminitis caused by high insulin is different from laminitis due to other causes.  Activation of enzymes and inflammatory reactions are not part of the picture.  This probably explains why the usual treatment with NSAIDs [nonsteroidal antiinflammatory drugs] like phenylbutazone has little effect.  There is help though.

Blanketing the horse when temperatures dip below the equine thermoneutral temperature of 45 F helps avoid cold stress. Keeping the lower legs wrapped and feet protected inside lined boots also helps maintain normal circulation to the distal extremities.

Adaptogens are herbs which support a healthy response to stressors like cold weather. Jiaogulan [Gynostemma pentaphyllum] is a particularly good choice because this herb is also known to support production of the vasodilator, nitric oxide. Jiaogulan should be given twice daily, preferably before a meal. Most horses love the taste and will lick it up as a powder or paste.

L-arginine is the amino acid precursor for nitric oxide and can be supplemented along with the Jiaogulan. L-citrulline is another amino acid that the body converts to L-arginine for nitric oxide production.  Cold stress also results in considerable oxidative stress and antioxidants help neutralize these free radicals.

Finally, acetyl-l-carnitine supplementation can be indicated for support of normal nerve function and glucose handling.

When you understand the trigger of winter laminitis you can support the horse with simple measures to minimize cold stress and maintain normal blood flow to the feet.

Eleanor Kellon, VMD



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Pica is defined as ingestion of items with no food value over a period of at least one month. This is actually normal in the young of all species. Horses rarely fit the description of chronic consumption except for devoted wood chewers but sporadic eating of dirt or manure is fairly common.

Bark stripping yields negligible nutritional benefits and could be considered a form of pica.

Most formal research has been done in humans and may not be directly relevant to the horse but at least they can provide feedback.  Pica is seen in a number of developmental or psychiatric disorders. It is also commonly associated with anxiety, which may fit well with the equine picture.

In people, an association has been noted between pica and pregnancy and/or anemia. However, this has been difficult to tease out from other associated factors.  For example, dirt eating during pregnancy is a cultural practice in some developing countries where dirt is actually sold by street vendors.

Detailed analysis of many studies has been unable to settle the chicken or egg question regarding a connection between mineral deficiencies and pica. One problem is that dirt eating often focuses on clay (same is true of animals) and clay can bind nutritionally beneficial minerals and/or be a source of toxic ones like lead or aluminum.

Another interesting association with pica reported by humans that we really can’t confirm or rule out in animals is that it can be caused by nausea.  Clay is the obvious choice for relief of any GI upset and is a common ingredient in both human and animal products for both gastric upset and issues with diarrhea and gut toxins.  Clay binds many fungal and bacterial toxins and is a major ingredient in Kaopectate.  Horses are certainly no strangers to GI upset in many forms.

Eating feces (coprophagia) should be in a special category because it does have some nutritional value. It is so common in rats and rabbits that the practice is considered a normal behavior used to obtain protein and minerals that are not well absorbed from the large bowel and would otherwise be wasted. In fact, deficiencies can develop if they are prevented from eating feces. It is also a perfect prebiotic that is not only rich in live organisms but also precisely the types the animal needs.

Coprophagia is also normal in foals, piglets and even young ruminants like calves and sheep.  Dogs are notorious for eating the fecal matter/manure of a variety of other species.  Cats will eat their own feces out of hunger or boredom (reduces or stops if they are allowed free choice access to food) or when vomiting. It’s unclear if they are eating feces to induce vomiting (e.g. hairballs) or to attempt to recover nutrients.

So, what do we actually know about aberrant feeding behaviors in horses?  Two studies in horses from the late 1970s identified low protein intake as a trigger for coprophagia which fits with data from other species. No solid connection with mineral deficiencies has been documented although by observation dirt eating may increase in ill horses and could be an instinctive but nonspecific drive for minerals. Horses may also eat dirt or lick metal when seeking salt.  Pica as an outlet for anxiety, boredom or not having food available is likely an issue in many scenarios, as is dirt eating related to GI upset.

Fortunately, most of the possible causes are benign.  Small net hay feeders, toys, plenty of exercise and a quality diet may help prevent pica. However, if anything seems “off” when your horse starts odd eating behavior it’s best to involve your veterinarian.

Eleanor Kellon, VMD



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Cold Weather and Stiff Horses

Research has proven that exposure to cold causes increased stiffness in both muscle and connective tissue, including tendons and ligaments.  A recent human study also confirmed that dampness (relative humidity) is correlated with increased joint pain and this effect is worse when the weather is also cold.

The effects are magnified in older horses.  “Sarcopenia of aging” is age related loss of muscle mass which gets worse if the horse is not regularly exercised.  Age also causes increased tendon and ligament stiffness/loss of flexibility and lesions develop in the core of flexor tendons.  To top it all off, muscle is less strong in the cold because energy generation becomes less efficient, allowing more energy to escape into the cells as heat.

The end result of all this in its mildest form is horses which have a wooden, stiff movement. In the worst case scenario they are so severely affected that getting up from a down position becomes very difficult or even impossible.  Fortunately, this scenario isn’t inevitable.

All horses require an adequate place to shelter from precipitation and winds in the cold. For the horse prone to cold related stiffness, it’s critical. Blanketing to preserve body heat and support muscle energy generation and soft tissue flexibility is also desirable. For horses prone to stiffness, don’t wait until they are shivering.  If the hocks or knees are known to be an issue, look into Neoprene or lined boots to keep the joint warm when the horse is confined and/or overnight.

Wraps can also be used for the lower legs to protect those joints and the tendons and ligaments. Lined shipping boots with Velcro closures are often a good option because they cover from below the knee to coronary band, are very warm and can’t cause problems related to slipping and too much pressure.  Hoof boots with a liner between the bare rubber and the horse’s sole are also helpful.

Horses with obvious areas of discrete muscle/tendon/ligament involvement rather than a stiff all over picture can benefit from use of a topical containing capsaicin.  Mint in the formulation will increase the warming effect.

Supplements to support homeostatic defenses against cold-related oxidative stress can be very helpful. Look for ingredients like Devil’s Claw, Cat’s Claw, Turmeric, Boswellia and Yucca. On the nutrient end, good choices include MSM, berries, Resveratrol, Quercetin and Grape Seed Extract.

Finally, bolster normal joint cartilage maintenance with the big three of Glucosamine, Chondroitin and Hyaluronate plus connective tissue support in the form of Green-Lipped Mussel and hydrolyzed collagen.

Winter is a stress on any horse, even moreso for seniors. Supportive measures don’t have to be complicated if you understand the physiology and the tissues you need to target.

Eleanor Kellon, VMD



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Co-Products, not By-Products

There is a trend these days to label many highly nutritious feed ingredients as worthless wastes.  This particularly falls on anything that might be classified as a by-product, including beet pulp, wheat mids, soybean hulls and distiller’s dried grains.

Do you consider such things are semolina, wheat germ, rice bran, linseed meal, corn meal, couscous, molasses, copra (coconut meal), Psyllium, and bran cereals to be by-products? Probably not, but like the ingredients listed first they are all co-products generated during the processing of a food to remove certain portions of it.

        Psyllium products are made from the thin coat surrounding Psyllium seeds

Soybean meal, like all seed meals, is a co-product of the oil extraction industry. They have all of the protein, carbohydrates/fiber, vitamins and minerals of the original food, just not the high fat. As a plus, reducing the fat considerably boosts the protein percentage in the meal.

Some of the prejudice against co-products likely arises from unfamiliarity. You won’t find beet pulp on the shelf in human food stores because people can’t digest it – but horses can. Beet pulp is a low sugar, essentially zero starch, high soluble fiber that is easily fermented in the horse’s hind gut, is prebiotic and yields more calories/energy than hay. The same is true of soybean hulls.

Some co-products have unique characteristics. Feeding distillers’ or brewers’ dried grain instead of corn, etc. means starch and calories have been reduced to very low levels via fermentation of the grain but palatability is retained and protein is significantly higher than in the grain.

Psyllium (Plantago) husks are another specialty co-product. They are the thin outer coating on Psyllium seeds and are rich in mucilage, a form of soluble fiber.  When fed on an intermittent basis they are an effective way to enhance sand removal from the colon. When fed on a daily basis they become a prebiotic as the hind gut organisms adapt and begin to ferment them.  An added bonus is that wet Psyllium gives a distinctly slippery/slimy coating to a meal which makes it easy to swallow.

Co-products may be criticized because they are not whole foods but the whole foods mentality can be carried too far. Do you eat peanut shells or walnut hulls when you eat those foods?  Lemons, bananas or oranges with the peel? Of course not, because they are largely undigestible and/or unpalatable.

Co-products may actually have enhanced nutritional qualities for the horse. Beet pulp, distillers’ dried grains, brewers’ dried grains are safer because of greatly reduced sugar and starch levels.  Seed meals have reduced calories because of fat removal and higher % of protein. Brans and seed coats have very good to high protein levels, low sugar/starch and are good mineral sources. Wheat co-products have all the concentrated nutrition of wheat without the starch, which was processed out to make white flour for people.

Not all co-products are appropriate for horses (e.g. oat hulls or cottonseed products) but those you find in feeds and supplements typically are. Be fully informed before you make a judgement call.  There’s a good chance your own diet contains co-products.

Eleanor Kellon, VMD



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Air Quality in the Barn

When the winds are up and temperatures drop we want our horses to be comfortable and protected. Nestling into a cozy stable may seem like a good solution but there are health risks lurking in a tightly closed up barn.

Fine particulate matter and fungal elements from stored hay and straw are a major source of respiratory irritation in barns with poor ventilation.

Horses with respiratory issues actually breathe easier in cold, dry air.  However, this winter advantage is lost when horses are confined to a poorly ventilated barn where humidity and particulate matter in the air is high.

An elevated concentration of irritants in the air causes measurable lung inflammation in all horses. There may or may not be a true allergic component. Continued exposure can lead to IAD (inflammatory airway disease) or RAO (recurrent airway obstruction) in susceptible horses. These conditions have a considerable impact on the horse’s comfort and performance. There may be increased risk of infectious lung disease or irreversible damage in chronic cases.

A variety of airborne substances have been implicated. Ammonia from bacterial breakdown of urea in urine is a well documented lung irritant in a variety of species. “Organic dust” is also an offender. This includes microscopic particulate matter from mites, plant material (e.g. beta-glucans), feces, bacteria and their products (endotoxin) and fungal spores.

Keeping stalls clean and the building well ventilated are the first steps in reducing exposure. Using wood chips or synthetic bedding (e.g. paper based) reduces plant and fungal matter but must be used in all the stalls. Horses are also exposed when hay or straw are stored in the same building, even in a loft.  Horses with clinical signs should have their hay and bucket fed meals thoroughly wet down. Always strive to remove horses from the barn when stalls are being cleaned and aisles swept.

These measures will go a long way in reducing risk of developing lung disease and reducing breathing difficulty in horses that already have it but they cannot completely eliminate exposure and some horses will need more help.

Medical treatment includes a variety of systemic or inhaled agents including corticosteroids, bronchodilators and mucolytics.  There are also supplements you can use to assist the horse’s body in normal respiratory function and maintaining healthy tissues.

Exposure to lung irritants and activation of the immune system results in considerable oxidative stress. Vitamin C is an important antioxidant in the lung and studies have shown low levels of vitamin C in the lung fluid of diseased horses. Oral dosages of 4.5 to 10 grams/day are used for the average size horse. Antioxidant activity can be boosted by pairing it with sources of plant antioxidants such as Grape Seed and citrus bioflavonoids.

Nagging coughs are a common sign of both infectious and noninfectious lung disease. The coughing itself is also irritating. Human over the counter lozenges and chest rubs take advantage of the ability of aromatic oils like camphor, eucalyptus, menthol and orange to help maintain open, relaxed airways with thin mucus that is easily cleared. They work the same way in the horse and equine specific products are available. Pastes are easiest to administer.  Look for a soothing base with ingredients such as Aloe vera, apple cider vinegar, glycerin and honey.

Spirulina, 20 grams twice daily, helps the horse maintain lung homeostasis by stabilizing mast cells and supporting a balanced immune response.  Jioagulan supports control of stress responses and maintenance of relaxed bronchial tone. Omega-3 fatty acids from flax seed provide the raw materials for normal balancing of inflammatory reactions. MSM also assists the body in balancing its responses to triggers of lung irritation.

Controlling exposure to lung irritants greatly reduces your horse’s risk of developing chronic lung disorders.  If you do have to deal with signs of lung irritation there are many options, including nutritional support for normal lung function.

Eleanor Kellon, VMD

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Spirulina for Insulin Resistance?

First, I’m a huge fan of supplemental Spirulina platensis and have been for many years. There has been buzz this fall surrounding a study that supposedly shows Spirulina supplementation reversed Equine Metabolic Syndrome [EMS].

Spirulina platensis under the microscope.

The study by Nawrocka et al appeared in the August 2017 issue of the journal Marine Drugs. In the first part of the study the researchers quantified fatty acids, amino acids and other components in the Spirulina. They also confirmed its previously documented antioxidant benefits in cultured equine cells.

The second part of the study utilized three groups of horses – normal, EMS and EMS on a Spirulina supplemented diet.  After 3 months on the experimental diets 5 of 6 horses in the EMS + Spirulina group tested normal on a CGIT – combined glucose and insulin tolerance test. A popular equine lay magazine reporting on this study stated this indicates the horses were negative for EMS after 3 months but this is not accurate and also not what the study said.

The CGIT test is not reliable in horses.  It has poor sensitivity, which means there is the potential for many falsely negative/normal results.  It also has poor repeatability. Results from one test date can be very different from another in the same horse. The bottom line is that we can’t rely on those findings but it should be noted significant changes only occurred in the EMS horses supplemented with Spirulina.

Among the other changes noted after three months in the Spirulina group was weight loss. However, the horses were on a diet of 1.5% of the body weight in timothy hay which alone could explain the weight loss noted.  The EMS horses not given Spirulina did not have a weight loss but the article did not give details about the differences between the pelleted feeds the EMS horses in the two groups received. The EMS + Spirulina group also showed a reduction in the cresty neck score, but not to a normal level.

Four out of six of the EMS + Spirulina horses had a significant reduction in their insulin levels while the EMS group not on Spirulina did not. The insulin levels were still very abnormal, but lower. Again, it is unknown to what extent differences in the composition of the pelleted feeds given to the two EMS groups might have contributed.

Leptin, a marker of insulin resistance independent of insulin and glucose dynamics, was not changed by Spirulina supplementation.

The study did not give the actual dosage of Spirulina that was used, or whether the horses were monitored to see if they were actually consuming the whole dose. This is a significant point because Spirulina is not particularly palatable.  In my experience, when horses are presented with Spirulina pelleted into a palatable base and mixed into their usual meal 1/3 will refuse to eat it, 1/3 eat slowly and may not eat it all while another 1/3 will consume it readily.

This isn’t the first time Spirulina has been investigated in metabolic syndrome/insulin resistance. Benefits have been shown in humans and laboratory animals. However, there are significant differences in the syndrome between these species and the horse.

The take home message is there are many questions regarding this study. Even if the findings are reliable, it’s not a cure by any means.  Controlled calorie intake using a diet of low sugar + starch hays with small amounts of similarly low sugar + starch carrier feed for supplements, plus as much exercise as possible, remains the foundation of management of Equine Metabolic Syndrome.  For details based on over a decade of following thousands of these horses please visit http://www.ecirhorse.org.

Eleanor Kellon, VMD


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