Silver Bullets are for Werewolves

I have been a strong proponent of the role of nutrition in health and optimal function for four decades but with the understanding that while it is pivotal it’s not the sole answer to everything.  Scientifically unrealistic claims for the benefits of supplements mislead owners/caretakers and end up eroding confidence in the power of nutrition.

No silver bullet supplements can guarantee safe grazing for all horses.

Some things are straightforward. Pregnant mares with severe selenium deficiency can give birth to foals with white muscle disease. Supplement those mares with adequate selenium when pregnant and this doesn’t happen. It’s rarely that simple.

For example, there’s been a mini proliferation of “topline”/muscle supplements lately. They typically are 30 to 60% protein and deliver essential amino acids (the building blocks of protein) in dosages ranging from miniscule to sufficient to correct a deficiency state in some circumstances.

The problem is you cannot build muscle just by feeding protein unless there is a dietary deficiency, and there certainly is no supplement that can specifically target the topline. There are several potential causes of topline wasting that cannot be fixed with protein. These include aging, Cushing’s Disease, chronic lung disease, poor saddle fit, Equine Motor Neuron  Disease, EPM and Equine Polysaccharide Storage Myopathy.

The back and croup are also normally covered by a thick layer of fat. Weight/fat loss alone will cause lack of definition along the topline.  The other key “ingredient” to building muscle bulk in any location is exercise.

Then there is the persistent myth that there is a widespread issue with hindgut acidity and hind gut ulcers, with a corresponding assortment of supplements that claim to address it.  The pH of the hindgut normally varies with diet – highest with hays, lower with pasture and hay/grain diets.

There is not one shred of credible evidence showing these normal  variations cause ulcers, pain or behavioral and gait issues. The most recent study that set out to investigate colonic ulcers and causes found ulceration in 12 of 56 (21%), 9 of which were clearly caused by parasites. Only 3 horses (5%) had colonic ulcerations with no clear cause visible but the health and drug (phenylbutazone) history of those horses was not known. http://onlinelibrary.wiley.com/doi/10.1111/evj.24_12732/full

Worse yet are claims for supplements that will let you put any horse out on spring pastures without having to worry about laminitis. Pasture-associated laminitis is caused by higher starch and simple sugar levels in the new growths of grass. Supplement ingredients that address hindgut fermentation (e.g. hops) are irrelevant. Ingredients supporting blood sugar control in humans are also useless since insulin is the problem, not high blood sugar.

It’s true that mineral nutrition is important to the health of hyperinsulinemic horses, but there is no evidence that mineral deficiencies  can actually cause hyperinsulinemia or that correcting those deficiencies or megadosing minerals alone can protect from high insulin levels and laminitis. Please don’t be fooled.  The only way to protect horses prone to hyperinsulinemia from pasture associated laminitis in the spring is to keep them off the pasture.

It’s human nature to want a quick fix, a simple solution to make everything normal. Unfortunately, that’s rarely possible. Nutrition and appropriate supplementation is just one piece of the puzzle. Silver bullets are for werewolves.

Eleanor Kellon, VMD

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Loving Mares

In my younger (OK, MUCH younger) days, I didn’t like mares. They seemed unpredictable and difficult compared to geldings, or even stallions. I was wrong.

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In the feral society of horses, mares have tremendous responsibilities. The stallion is the lookout, will move them in times of imminent danger and directly take on predators but the day to day social management falls on the mares. The band moves whenever and wherever the alpha mare directs them. She also maintains order. All the mares below her fall into a defined social framework and do their part in policing the band.

The high level of responsibility that mares have carries over into their behavior in domestication. Mares are very sensitive to, and upset by, chaos and turmoil of any kind. They do not respond well to yelling, confrontations, disruptions or physical force. Their goal is peaceful coexistence with well being for themselves, their foals and their band mates.

The mare’s life revolves around basic needs. When hungry, seek out food. When thirsty, drink. When tired, rest. Sounds simple but unless you look at their world that way it can lead to misinterpretation.

I remember a young Standardbred mare we took to her first race on a rainy day. She was fine in the paddock but when driven out to go to the post parade and the rain hit her face she immediately planted herself, turned around and tried to go back inside. The look on her face to me was obviously “It’s raining! What’s wrong with you people?” She didn’t think too much of the idea that she should stay up with the field and have mud slung in her face either. She got over it once she learned to enjoy racing. The important thing was to recognize the behavior for what it was, not to overreact or overanalyze. She wasn’t balking, sulking, being a prima donna or any other dire interpretation. She was just trying to get out of the rain.

A common complaint is that mares do not perform as well or consistently when in season. My first advice is – get over it! Understand that this is as basic a drive for survival as are hunger and thirst.When ovulating, announce it and breed.

Regumate (synthetic progesterone) administration has been the go-to solution for eliminating estrus behavior. It doesn’t stop cycling but because estrus is triggered by drops in progesterone it does block the outward manifestations. Drawbacks are that some mares become dull, irritable and listless (if you have ever been pregnant, you can identify) and progesterone can worsen insulin resistance.

You can also work around this issue with management changes. Don’t expect her peak effort. Do keep her distracted by exercises including many changes of direction, cavaletti, etc. or go for a relaxed cross-country walk. Picking your battles carefully is most likely to get some behavioral modification. If she vocalizes occasionally, ignore this. A little urine squirting when in the aisle is really not a big deal either. If this is too much for you to deal with, get a gelding.

A mare treated calmly and fairly will be a willing partner but if you can really earn her trust and be admitted to her world you’re in for a special experience. One of my favorite horses of all time is a mare that came to us as the stereotypical “bitchy mare”. She was actually dangerous, would try to kick or bite anyone within range.

Her former trainer revealed he never entered her stall without a whip and had used strong arm tactics to deal with her – unsuccessfully. Observing her the first few days one thing was abundantly clear. She was miserable. After some firm but gentle definition of boundaries it was possible to give her a good examination. She had multiple physical problems – feet, joints, back, muscle. All work was suspended and she was given time to heal.

With respectful handling and her pain receding she was a new horse. She would yell in welcome and often “talk” when being groomed or treated.

Because she tended to overdo it when on turnout, we got her a goat as a companion. She became so attached she would stay by the goat and buck in place rather than tear around. Another time a litter of puppies broke into her stall and she was found standing like a statue with puppies jumping on all four legs. When on the home farm, I could leave her stall open for her to graze as she pleased because she didn’t have anywhere else she wanted to be. She was also the fastest racehorse we ever had.

There are many other stories, and anyone who has loved and been loved by a mare has a collection of their own. I just want to say that anyone avoiding mares thinking they are too difficult is really missing out!

Eleanor Kellon, VMD

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Nutrition for Advancing Pregnancy

In the last half of pregnancy the foal grows from the size of a small dog to an average 100 lb foal. Nutritional needs ramp up significantly in late pregnancy and calories are the least of the concerns.  This means keeping the mare at a good weight can still result in important deficiencies.

The mare in late pregnancy needs 28% more calories but 41% more protein. Calcium and phosphorus requirements are increased 80%, vitamin A 100%, vitamin E 60%. If you keep her diet the same as when not pregnant, just increase calories by that 28%, she will end up short on all the other nutrients.

How are you faring with providing for your pregnant mare? The answer lies with the quality of your hay but few people focus on that so let’s look from another angle. Most people describe their feeding program in terms of their bagged feed. If you are feeding 5 lbs/day (roughly 5 quarts by volume) of a supplemented and balanced 14% protein feed you are providing roughly 35% of your mare’s late pregnancy protein and mineral needs if her prepregnancy weight was around 1100 lbs.

If you add 1 lb/day of an at least 25% protein/mineral supplement she will be getting about half of the protein she needs and as much as 75% of minerals (depending on the product) from the combination of grain and protein/mineral supplement. This is a good start on minerals but quite a way to go yet on protein. This mare will also be eating 10 to 15 pounds of hay, which should more than fill in the gaps in minerals but will still leave her short on protein unless it is at least 11% protein.

While it is very common to build the diet for a pregnant mare on fairly high grain feeding as above, it’s expensive and there is another way. A good quality grass hay, with a calorie level of 0.9 Mcal/lb and 11% protein can support an 1100 lb mare through pregnancy at only 24 lbs/day even in the last month. Calorie needs are met and protein actually exceeds requirements. An equine nutritionist can advise on mineral supplementation needed based on the hay analysis.

Feeding a pregnant mare nothing but good quality hay or pasture may seem impossible because we are so conditioned to think of the horse’s diet in terms of the bagged feed, “necessary” for protein, vitamins and minerals. However, because grains are so calorie dense they need to provide at least 2.5 times the protein present in hay to just break even. If a pound of a bagged feed = 2.5 lbs of hay on a calorie basis, it would have to be 25% protein to provide as much as the 2.5 lbs of a 10% protein hay. Even making allowances for better digestibility of protein in the grain mix, they still come up short.

What your mare lacks in her diet she will take from her body. This is a nice fail-safe for the developing foal but not at all good for the mare long term.

What if your hay changes too frequently to analyze and you are not sure if the quality is adequate? Add a protein/mineral supplement, 1 lb/day for the first half of the pregnancy, 1.5 to 2 lbs/day after that for the average size mare.

When feeding this it is unnecessary to feed a supplemented bagged feed and actually causes excessive mineral intake and potentially toxic combined levels of vitamin A and D. If she is eating sufficient hay – 24 to 30+ lbs/day in late pregnancy – there is no need to feed grain. Just feed the protein/mineral supplement. If she is not eating enough hay, you can make a simple feed mixture that will be balanced for major minerals and cost you far less. Examples include:

  • 4 oz soybean meal, 1 lb each beet pulp and oats
  • 4 oz soybean meal, 2 lbs oats, 1 lb alfalfa pellets
  • 4 oz soybean meal, 1 lb each alfalfa pellets and wheat bran
  • 4 oz soybean meal, 1 lb alfalfa pellets, ½ lb rice bran (without calcium added)

As always, introduce diet changes gradually to avoid digestive upset. Finish off the diet with 1.5 to 2 oz of salt/day and 2000 IU of vitamin E in oil.

Mare on pasture? You can’t measure how much she is eating but you can keep a close eye on body condition. Skin is stretched thin over the ribs in a heavily pregnant mare so this area cannot be reliably used. Instead, pay attention to the fullness of the rump, the neck and the topline.

Eleanor Kellon, VMD

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Myths and Misconceptions about Insulin Resistance/Metabolic Syndrome

It always takes a while for textbooks, veterinary schools and practitioners to catch up with the best published research. Magazines and news feeds often focus on whomever has a better and louder PR network. There are also companies and individuals that seek to capitalize on owners’ concerns, offering products or services that may even claim to be science-based but are not.  The end result is a lot of advice that at best is not helpful and at worst is harmful. These are a few of the latter.

Short chain (or any length) fructans cause insulin to rise.  This is sometimes presented as a need to look at starch plus WSC (water soluble carbohydrates which includes some fructans) versus starch plus ESC (ethanol soluble carbohydrates = simple sugars only) when evaluating the safety of a hay or other food item.  This misunderstanding can cause people to reject perfectly safe hay and waste time and money looking for hay which ends up being overly mature and nutritionally inferior in many ways such as digestibility, protein and vitamin/mineral levels. Look for ESC + starch less than 10% and don’t worry about fructan unless NSC [WSC + starch] is over 40%.

Insulin resistance is an inflammatory condition.  Metabolic syndrome in humans is associated with elevation of a number of inflammatory proteins called cytokines but the picture in horses is far less clear.  Suagee et al 2012 found no correlation between insulin levels and inflammatory cytokines like TNF-alpha and IL-6 that are elevated in IR humans. Vick et al 2007 found a correlation between IR and TNF-alpha levels but only in mares older than 20. No other cytokine changes.  Burns et al 2010 found higher inflammatory cytokine levels in the neck crest fat but no difference between normal and IR horses. Laminitis in IR horses is also not inflammatory. This is important because it explains  why the response to NSAID drugs for pain in IR horses is typically poor and why these drugs do not “treat” anything.

“Whole foods” can prevent/cure insulin resistance. It’s not too clear where this idea came from but I suspect it is referring back to the difference between how things like white bread versus whole grain products produce higher glucose and insulin spikes in humans. That’s true, and it’s also true that processed (e.g. extruded) barley and corn are more digestible to glucose. However, that does not mean that whole oats or whole corn will be safe.  They most definitely are not. It also does not mean that heat processed grains or co-product foods like brans or wheat midds cause IR. Food does not cause insulin resistance and many of these co-products are lower in sugar/starch and higher fiber than the whole food.

XYZ supplement or feed will make it safe for your IR horse to return to pasture.  All the evidence points to IR being an inherent part of the horse’s metabolic makeup. They are born this way. When food is scarce and poor quality IR is actually a survival advantage, but not for domesticated horses. Nothing can change the way the horse was born. Proper management will keep it from being a health issue but free access to grass is rarely possible. Grass is a living tissue and its levels of sugar and starch will vary. Things like type of grass, weather conditions, stage of growth, severity of IR, level of exercise influence how safe (or not) some degree of grazing may be but no supplement will make it safe for you to just turn an IR horse out on grass.  You may get away with it for a while but sooner or later there will be problems.

Glyphosate (Round Up) causes metabolic syndrome. All herbicides are potentially toxic but like all things potentially toxic there will be a dangerous level (dosage matters) and also predictable effects that are discovered in the course of toxicity studies. Glyphosate has been blamed for  just about any human medical condition you can think of. More recently, claims focused on horses including that glyphosate causes EMS. The proposed mechanism for this is glyphosate substituting for the amino acid glycine in cellular insulin receptors. Problem is, this is 100% speculation with zero evidence to show this happens and at least one formal study, Kim et al 1990, that shows it does not. The people making these claims have a “Dr.” before their name by virtue of a PhD but their area of expertise has nothing to do with physiology, biochemistry, medicine, toxicology or nutrition. Would you go to your dentist for advice on a hysterectomy or to your gynecologist for a hip replacement? Don’t take advice about food choices from a computer scientist. There are often benefits to organic foods but going non-GMO won’t eliminate equine metabolic syndrome.

If you want to read an excellent, up to date, scientific article on laminitis and insulin resistance written by researchers who actually work in the field, go to https://ac.els-cdn.com/S1090023317302290/1-s2.0-S1090023317302290-main.pdf?_tid=65e40764-09de-11e8-8008-00000aacb35f&acdnat=1517771331_25d95e37e7e00d7407fd1f0c0bad5dc3.

Eleanor Kellon, VMD

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Supplementing Old Hay

It’s the time of year when even last year’s hay isn’t so new anymore and hay is getting hard to find, leading many people to settle for hay that is actually 2 years old. Properly cured hay stores well in terms of the major calorie sources (fermentable fiber and other carbohydrates) but it does incur some important nutrient losses.

Freshly harvested hay is rich in a pigment called beta-carotene which is the major precursor of vitamin A. As hay ages, light and air take their toll on the beta-carotene. As levels drop, hay begins to lose its nice green color. This is a sure sign vitamin A value has dropped. Skin, eyes, coat, thyroid and ovaries are among the tissues most affected by insufficient vitamin A. Start supplementing with 20,000 IU of vitamin A when hay is 6+ months old, increasing to 40,000 IU when over a year old.

Vitamin E activity also drops with storage and is lost even more quickly than vitamin A. All horses eating hay rather than fresh green pasture should be supplemented with 1 to 2 IU/lb of body weight daily.  Alpha-tocopherol is the major biologically active form of vitamin E. If you use mixed tocopherols you will not be supplying enough alpha-tocopherol.

Both vitamin A and vitamin E are fat soluble vitamins and require adequate fat for absorption and transport. Fat is also required for the conversion of beta-carotene to active vitamin A. Curing and storage reduce the natural fat content of hay to 50% or less of the value in fresh pasture, primarily by loss of the fragile omega-3 fatty acids. High omega-3 fatty acid supplements, based on Flax and  Chia, help replace these losses.  Actual requirements of the horse are unknown at this time but daily supplementation of at least 2 to 4 ounces of these seeds is generally recommended.

Like vitamin E, vitamin C is rich in fresh pastures and very rapidly declines when hay is cured. The horse is capable of  synthesizing his own vitamin C but this may not be enough for optimal levels. It has been documented that blood levels of vitamin C drop sharply over winter and horses may benefit  from supplementation of 1 to 5 grams of vitamin C/day.  Vitamin C is an important cofactor for the production and maintenance of strong immune responses and healthy skin, lung and tendon/ligament tissues.

Finally, excessive loss of moisture over time often leads to crumbling of the leaf portion of the hay, visible as a layer of “fines” when the hay is handled. The more stemmy portions left behind are lower in protein, B vitamins and fermentable fiber. A higher percentage of minerals bound to the nonfermentable fiber can also reduce mineral nutrition.  Use of a full spectrum vitamin and mineral supplement formulated to complement the most common hay mineral profiles (e.g. low to no iron, low manganese) is good insurance.

Poor nutrition over winter is a common occurrence for the feral horse but there is no reason for the well managed domestic horse to have these challenges. Maintain optimal nutrition by understanding the deficiencies in older hay.

Eleanor Kellon, VMD

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Hormonal Laminitis – What It’s Not

At the NO Laminitis Conference last year I spent several hours talking about what insulin related laminitis is not. A paper just published in The Veterinary Journal (Patterson-Kane et al) called Paradigm shifts in understanding equine laminitis does the same thing.

Laminitis has always been incompletely understood. We have assembled a list of causes/triggers but did not really understand the mechanism behind the damage to the laminae.

One theory was that it was vascular. Compromised blood flow caused cellular damage or death. Others focused on infiltration by white blood cells and the inflammatory reaction. Most recently bacterial toxins gaining access to the body after damage to the lining of the  hind gut was proposed as the triggering event. The toxins activate enzymes called MMPs which then break down the basement membrane, a tissue that forms a bond between the secondary dermal and epidermal laminae. These are factors involved in laminitis caused by plant toxins, bacterial infections (e.g. retained placenta, “bastard” Strangles) and hind gut overload with starch or inulin. However, it is now recognized that approximately 90% of laminitis cases are caused by endocrine disease – high insulin levels.

Hyperinsulinemia is seen in Equine Metabolic Syndrome (EMS) and pituitary pars intermedia dysfunction (PPID), aka Cushing’s disease complicated by insulin resistance. With such a high percentage of cases being caused by hyperinsulinemia, it becomes extremely important to understand both how to control insulin levels and exactly how insulin causes damage to the laminae if we are going to effectively prevent and treat this type of laminitis.

Controlling insulin involves medication if the horse has PPID, as much exercise as possible and a diet where everything the horse eats has less than 10% simple carbohydrates – sugar (ESC) and starch. Fructan is not a sugar and does not enter into that 10% total.

As for the mechanisms underlying the damage to laminae, the logical place to start looking for those is to go back to what is known about other forms of laminitis. Studies have now found that with hormonal laminitis there is no activation of MMP enzymes or basement membrane destruction, no evidence of inflammation as an early event. These are important findings because they explain why NSAID drugs like phenylbutazone typically have little effect on the pain of hormonal laminitis.  Anti-inflammatories don’t “treat” anything when there is no inflammation.

One theory was that insulin resistance deprives the laminae of needed glucose but this was soon shown to be incorrect because these cells do not rely on insulin for glucose uptake. A current hypothesis being investigated is that the high insulin levels interfere with normal cellular reactions to IGF-1 (insulin-like growth factor 1) because IGF-1 cellular receptors can also be triggered by insulin, albeit much more weakly than by IGF-1. There is some evidence so far that IGF-1 activity is disrupted in hormonal laminitis but much more needs to be done to determine the consequences and whether this is actually a cause or just a reaction to tissue damage.

The one abnormality that is well documented is high levels of endothelin-1, the most potent vasoconstricting substance in the body. This is also a feature of human insulin resistance and type 2 diabetes, and explains the circulatory problems these people have. It also explains why many hyperinsulinemic horses experience hoof pain with exposure to cold and why treatments designed to increase nitric oxide, a vasodilator, are often very helpful with hormonal laminitis pain.

We have a lot more to learn. The first step is letting go of old information on other causes of laminitis because they simply don’t apply here.

Eleanor Kellon, VMD

 

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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.

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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.

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                 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.

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                  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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