Keeping a Spring in Your Older Horse’s Step

Horses are living much longer today and spending many more useful years under saddle.  Even so, age does take a toll on even the healthiest senior. I want to share a few things I have found to make an obvious difference in energy levels and feeling good attitudes.

Social Security.  No, I’m obviously not talking about a monthly check! Horses are social creatures and change in their social network can have serious consequences. Loss of a companion, moving and a drop in status within the herd are examples of common social stressors for older horses.

Horses have different sleep patterns and requirements than people but they definitely can become sleep deprived. They need to feel secure to sleep well so this is one area where issues often develop in older horses. If you notice your senior is never lying down to sleep, there’s a problem.  Try making sure he gets quiet time alone in a stall or with a trusted companion in a small pen with shelter.

When a horse’s position on the social totem pole drops, so does their chance of successfully competing for food within the group. What they do have access to may be lower quality foods (e.g. stemmy portions of hay) that others left behind. Eventually this leads to weight loss but long before that the horse becomes fearful and anxious. Their frustration may surface as aggression toward humans or resistance to work.  Keep a close eye on herd dynamics. If you see your senior being bullied around food be sure to give him enough time to eat by himself in a safe area.

Adaptogens.  Ageing in all species inevitably comes with reduced “vigour”, decreased capacity for work, lower energy levels, reduced immune function and less mental clarity in several areas.  Ageing is a complex process and at this point we have a better understanding of consequences than causes but in essence it is a blunted capacity of homeostatic processes to maintain a more youthful balance.

Adaptogens are nontoxic, naturally occurring plants that have the ability to support the body’s homeostatic responses to stressors of all types.  For example, the horse’s body reacts to the physical stress of regular exercise by adaptations in levels of key hormones like growth hormone and cortisol.  Within a certain physiological range, these changes enhance resistance to stress.  If levels fall above or below that optimum, resistance is lost and cellular damage can occur. Hormonal and DNA changes with normal ageing further erode adaptive capacities. Adaptogens assist the ageing body in keeping hormonal shifts within the resistance range and preserving key cellular functions like mitochondrial energy generation.

There is a long list of adaptogens to choose from. One that I particularly like for senior horses is Jiaogulan.  This is a vine from southern China which is widely used locally as a tea or vegetable. It is free of the extreme stimulation that often occur with Ginsengs but has a clear energizing effect in the older horse. It is highly palatable and supports a normal appetite, healthy gastric lining and good circulation.

Antioxidants. One of the major theories of ageing is that it is caused by cumulative damage from oxidative stress. Oxidative stress arises both externally from toxins, harmful metals, even the sun, and internally from metabolism, exercise, immune system activity. As the horse ages, this issue is compounded by a decrease in the ability to produce key antioxidants like vitamin C and glutathione, as well as the cumulative effects of a lifetime of suboptimal intake of key nutrients like vitamin E, selenium, copper and zinc.

If there is one time you want to keep your horse as oxidative stress free as possible, it’s as they age. This has to start with a balanced diet with adequate intake of all key antioxidant nutrients listed above.  Add vitamin C to the list, especially if the horse is not on pasture. Other nutrients of benefit are the antioxidants alpha lipoic acid and N-acetyl-cysteine which is also a precursor for glutathione. On the plant antioxidant side of things, benefit is derived from resveratrol/grape seed extract, bioflavonoids including quercetin, Boswellia, Turmeric, Ginkgo biloba (also a good pick me up for seniors) and Oregon Grape root.

While ageing brings its challenges, there is much you can do to support the horse when you understand what those challenges are. Seniors often respond dramatically to the correct supplements and there are few things more rewarding to witness.

Eleanor Kellon, VMD

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Lyme Disease in Horses

The number of human Lyme Disease cases is steadily increasing, with the CDC estimating there are at least 10X more cases than get reported. For every human case there are likely many more equine since they live outdoors and finding the tiny nymph stages responsible for most transmissions is extremely difficult on a horse even with meticulous grooming. Lyme Disease is most common in the Northeast (Maryland and Delaware and states north of there) and in the midwestern states adjoining the Great Lakes but has also been reported virtually anywhere except in the most arid desert regions.

The nymphal tick stages most likely to be transmitting Lyme Disease are much smaller than adults, about the size of a poppy seed.

Multiple studies have described antibody confirmation of equine infections with the Lyme organism, Borrelia burgdorferi. What we don’t know is how many infections actually produce symptoms. Researchers have been unable to experimentally produce symptoms even when it is confirmed several months later that the horse was successfully infected.

The most well documented consequence of Lyme in naturally occurring infections is neurological disease. Signs mimic other causes of meningitis or encephalitis and include anything from cranial nerve problems and sensitivity to touch to gait changes, ataxia and muscle loss. Borrelia can also invade the eye and produce a picture identical to “moonblindness”/periodic ophthalmia. The development of skin nodules has been reported at sites of bites from infected ticks. These are all issues that develop weeks to months after infection.

Signs of recent infection, fatigue and mild fever, are likely to be missed in horses and we can’t see the skin rash that is typical in people. Lyme may be treatable with a single dose of antibiotic in these early stages but horses are never diagnosed early. Additional signs that have been described in chronically infected horses include a shifting lameness, weight loss, depression, behavior changes and muscle pain.

Laminitis may also be seen in Lyme positive horses. It is often severe and when insulin elevations are detected they tend to be on the low end and disproportionate to the severity of the laminitis. These horses do not respond as expected to the usual dietary modifications.

The best diagnostic option available today is Cornell University’s Multiplex assay. This test can detect both early and late stage infections. Idexx Laboratories SNAP test is also accurate but may take up to 8 weeks after infection to become positive.

Treatment of Lyme disease in horses is complicated by the fact the infection is not detected until the late stages.  It is known from human medicine this makes treatment more difficult. Oral doxycycline or minocycline is usually prescribed but treatment may need to be repeated. Research has shown the best results with 28 days of intravenous tetracycline.

Prevention is always preferable but options are limited. Ticks can be discouraged in areas where horses are kept by keeping them dry/well drained, mowing grass, eliminating brush and piles of trimmings, avoiding wooded areas and fencing out deer.

All common ingredients in equine fly sprays have some tick repellent activity, with permethrin best against the species which transmit Borellia burgdorferi. However,  repellents and grounds keeping will never be able to protect the horse 100% from tick bites.

There is no vaccine commercially available for horses. It has been documented that horses develop antibodies in response to canine vaccines, and that antibody levels are better when the dose of vaccine is doubled, but antibody levels only persist for about 16 weeks. Horses would have to be vaccinated at least twice a year to keep their titers up and even then we don’t know for sure if those titers are protective. The safety of vaccinating a horse that is already infected is also unknown.

The threat of Lyme disease is likely to grow before it lessens. If you live in an area at risk for Lyme, always keep it on your radar. Positive antibody tests alone do not confirm the B. burdorferi infection is causing your horse’s issues but this puts it squarely on the list of possibilities for your veterinarian to consider.

Eleanor Kellon, VMD

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When Joint Nutraceuticals Are Not Enough

In a recent blog, https://wp.me/p2WBdh-za, I talked about the big three joint supplement ingredients – glucosamine, chondroitin and hyaluronic acid. They are components of the joint cartilage and/or synovial fluid that bathes the joint space and interior of tendon sheaths and bursas. These compounds can assist the horse’s body in maintaining a normal homestatic balance between degeneration and repair and many horses do extremely well on them. However, there are exceptions.

The joint nutraceuticals are most supportive in situations of normally encountered stress to the joint and all surrounding tissue – i.e. exercise.  The synovial lining is usually the first tissue to be stressed in the moving joint, with eventual production of thinner joint fluid and compromise of cartilage integrity if the body cannot balance the stresses with healthful and robust regenerative responses.

Joint movement may also strain tendons, ligaments and their attachment to bone (the enthesis).  If degenerative processes in the joint outweigh repair, the synovial membrane becomes thickened and can become pinched between the ends of the bones during exercise, bleeding into the joint cavity and irritating it further.

Cartilage also thins if normal maintenance processes cannot keep pace with the load. As cartilage thins, the cushioning effect is reduced and the joint space narrows. Bone in the area above the joint is irritated. Eventually there can be bone on bone contact rather than the protective cap of  cartilage normally present.  This causes further irritation and bone begins to proliferate in an attempt to stabilize the joint.

Helping the horse’s body to restore homeostasis in the face of all these processes in different tissue types may benefit from more than the usual joint nutraceuticals. There are numerous food components, individual nutrients and plant-based naturally occurring compounds which normally assist in maintaining homeostasis in remodeling and inflammatory pathways.

They accomplish this in several ways. Some, like vitamin C, are necessary cofactors in tissue formation. Others are either direct antioxidants or components of key antioxidant enzyme systems.  Free radical generation is an inevitable consequence of exercise and normal tissue housekeeping but when unbalanced can be harmful.  Still others may normally influence specific pathways or even gene activity.

These useful substances include Yucca, Devil’s Claw, Turmeric, Boswellia, Golden Rod, Astragalus, White Willow, Perna Mussel, Cat’s Claw, Golden Rod, Phellodendron, Fever Few, Egg Shell Membrane, Hydrolyzed Collagen, fatty acids, Silica, Boron, Vitamin C, essential amino acids, B vitamins, copper, zinc, Bioactive Whey, MSM, Resveratrol and other flavonoids abundant in brightly colored fruits.

Horses most likely to benefit from more comprehensive support are animals which are older, previously injured or working heavily. Health and performance are all about  homeostasis. There are many tools in your tool box.

Eleanor Kellon, VMD

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Nutrition for the Senior Horse

I’m old enough to remember when a 10-year-old horse was considered aged. Advances in health care and a growing respect for the value of experience and a mature temperament have changed that. Many horses are now active into their late teens or 20s and may live for a decade or more beyond that.

However, time seems to take an inevitable toll on any species. Are there special nutritional needs for the senior horse?

There is nothing you have to change simply because of the horse’s age.  If he is holding weight well, looking good and has good energy, don’t change a thing.  That said, there are some things to look for as the horse ages.

Dental care is often emphasized for keeping older horses in peak condition but the truth is there are many seniors whose teeth show no obvious issues but they begin to lose weight.  This is likely because the angle of the chewing surface, and the force that can be generated, changes with wear and dental work.  A typical history is that they do fine on pasture, which is soft and easy to chew, but will lose weight on hay.

Some of these horses only need a switch to chopped hay. Others will respond to a diet of pelleted hay and concentrate, preferably fed well soaked or even soupy. Hay should still be fed for chew time, but the horse will need from 50 to 100% of his calories to come from the soaked foods.

Older horses often have a reduced number and diversity of microorganisms in their hind gut. This issue may actually overlap with the chewing problems above since fibrous feeds need to be well processed for fermentation to be efficient. Signs of this issue may include lean body condition, abdominal distention, soft manure or fluid released around fecal balls.

Chopped or ground hays are actually prebiotic since they give the organisms something they can more easily process. Highly fermentable fiber sources such as beet pulp, psyllium husk, soybean hulls and complex plant carbohydrates boost the prebiotic value. High potency probiotic supplements can also help – but only after  their “food” in the form of prebiotics above are already in place.

You may hear that older horses need more protein but their requirements are actually not different. It’s their ability to utilize the protein that may change. In other species, age may come with reduced production of stomach acid which is called achlorhydria. Stomach acid plays a key role in the first step of protein digestion. Production of digestive enzymes by the pancreas may also drop with age.

None of this has been specifically investigated in the horse but provision of digestive supplements with protease activity and adding vinegar to meals may help a horse that seems to be losing muscle mass. It is also important to regularly check for PPID – pituitary pars intermedia dysfunction, aka Cushing’s Disease – because this is a common disorder of older horses and muscle loss is a hallmark.  Additionally, regular exercise has been found to be protective against the muscle loss that naturally accompanies aging.

Correct mineral nutrition may be as important for the senior horse as the very young horse. While issues such as decreased bone strength and waning immunity have their roots in hormonal changes and DNA decay, they can be greatly worsened by mineral deficiencies and imbalances. Of all the factors, this is the one that is completely within our control.

Aging appears to be accompanied by a reduction in all the body’s basic ‘housekeeping’ functions such as production of vitamins, enzymes and antioxidants. A well rounded vitamin supplement is therefore cheap insurance and of more importance for older horses.

There’s no reason today’s horse cannot enjoy good health well into his second decade. Nutrition plays an important role in this and gives us a powerful tool for supporting the senior horse.

Eleanor Kellon, VMD

 

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How Joint Supplements Work

The first joint supplement for horses came out in the 1980s and was a chondroitin sulfate only product, followed by products containing Perna (green-lipped mussel). In the early 1990s, a patent was granted for the first equine combination joint supplement containing glucosamine, chrondroitin sulfate and manganese.  The market has grown tremendously since then, and with good reason.

It would be amazing if an animal the size and weight of a horse didn’t develop joint stress with what we expect of them. The stress is also cumulative so that even horses that are not upper level athletes can eventually develop joint issues over time. Things like being overweight, poor/imbalanced hoof care and less than perfect conformation also contribute.

Fortunately, the horse’s body is equipped with ways to balance these normal challenges to the joint and we can support efforts to do so by providing the correct nutrients.

Joint health begins with providing the young horse the materials needed to develop strong bones and joints. This requires correct levels and ratios of minerals including ultratrace minerals like boron and silica and good protein intake with adequate essential amino acids as the base. Whey and hydrolyzed collagen are rich sources of key amino acids for connective tissue such as joint cartilage and for bone. Methylsulfonylmethane (MSM) may assist in maintaining a balance between cytokines involved in breakdown, remodeling and repair. Vitamins C, D and K play pivotal roles in cartilage and bone formation.

The three most familiar ingredients in joint support supplements are glucosamine, chondroitin sulfate and hyaluronate (hyaluronic acid). All three are naturally occurring components of healthy joint fluid, cartilage and the connective tissue matrix of bone. In addition to being structural elements in these tissues, they also serve important homeostatic functions.

Glucosamine has been found to support the expression of enzymes synthesizing hyaluronic acid as well as components of cartilage and help maintain balance between the activity of cells which break down versus build bone. Glucosamine also facilitates a healthy balance between cytokines favoring tissue destruction and those which repair and build.

Chondroitin sulfate has a similar action in supporting a healthy anabolic (builds) catabolic (breaks down) balance.  In fact, the actions of glucosamine and chondroitin complement each other.

Hyaluronic acid is a major contributor to the slippery, lubricating properties of joint fluid and it has many other functions, including the support of cell division and participating in normal clean-up and repair activities. Its presence in the joint cartilage gives it fluid holding capacity and resilience.

Vitamin C is critical to health of both bone and cartilage as well as soft tissues of all types because it plays an essential role in the formation of collagen, the basic protein of all these structures. Horses can manufacture vitamin C but it is unknown how well they compensate when requirements are high.

A number of herbs have been used for joint support, including Devil’s Claw, Boswellia and Yucca.  They all have in common antioxidant actions and support of a healthy homeostasis between anabolic and catabolic activity.

Your horse’s skeletal system takes a pounding every day. Supplementing the nutrients which support his ability to deal with these inevitable challenges and maintain healthy bones, joints and connective tissues is one of the best decisions you can make.

Eleanor Kellon, VMD

 

 

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Mini Nutrition Quiz

As promised, here are the answers to the nutrition quiz.

1. The first thing calculated in designing a diet is the calorie requirement. Once you know that, you determine how much of each element of the diet to feed. After you know how much you will be feeding you can calculate how much protein, fat, minerals and vitamins that is providing.

2. Iron is by far the mineral present in greatest excess in most diets. I’ve never seen a diet where iron needed to be supplemented.

3. There are many nutritional issues that may show up as poor hoof quality but the most common is trace mineral imbalances and/or deficiencies. The healthier, tighter growth at the top of this horse’s hoof occurred after mineral balancing with no other changes.

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4. Sulfur-containing amino acids are the most important source of sulfur in the diet. The horse can also absorb and utilize sulfates. Contrary to popular opinion, sulfur from MSM does not become incorporated into body tissues. It is absorbed easily but the sulfur it contains is all excreted.

5. None of those listed factors will cause inflammation. Inflammation only occurs in reaction to something like an injury or illness. The diet may cause an imbalance in the homeostatic mechanisms the horse’s body uses to balance inflammation but it can not actually cause inflammation.

6. The answer is False. Balancers may or may not provide enough supplementation to make sure individual requirements for nutrients are met, thus avoiding primary deficiencies, but secondary deficiencies often remain. A secondary deficiency is when the ratios between minerals are off, allowing minerals present in high amounts to essentially crowd out those in low amounts.

7.  Chloride is the electrolyte deficiency which causes alkalosis. Alkalosis is an excess of bicarbonate ions. To maintain electrical neutrality, the body strives to balance this equation: sodium + potassium = chloride +  bicarbonate. As chloride drops, bicarbonate must go up. This causes more binding of ionized calcium which interferes with muscle and gut function or can cause “thumps”.

8. The answer is all of the above. Fresh grass has more water, vitamin E and vitamin C than hay. If it is a fructan producing species, it also has more fructan when live pasture as the grass continues to metabolize fructan stores after being cut.

9. Again, the answer is all of the above. Deficiencies of iodine, selenium, copper and zinc are very common.

10. Horses differ in the way they absorb calcium. In other animals, calcium absorption is hormonally regulated but the horse freely absorbs calcium and excretes any excess in the urine.

11. Lactating mares have a higher dietary protein requirement than any other age, class or use. Failure to provide it compromises her muscle mass but she can also break down key tissues like tendons and ligaments to free up the protein she needs to make milk.

Eleanor Kellon, VMD

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Test Your Nutrition Knowledge

Nutrition is a specialty like any other scientific field. Despite this, it’s common for people with no qualifications to offer nutrition advice. Many things you hear or read over and over again can be wrong.  Take this mini quiz to test your own equine nutrition knowledge. I’ll post the answers tomorrow.

When building a diet and deciding how much to feed, the first thing to be calculated is always:

  1. calorie needs
  2. protein needs
  3. fat requirements
  4. starch and sugar levels
  5. minerals

The mineral most likely to be present in any diet at levels far exceeding requirements is:

  1. calcium
  2. phosphorus
  3. chloride
  4. iron
  5. copper

The most common nutritional factor contributing to poor hoof quality is:

  1. low protein
  2. fatty acid deficiency
  3. trace mineral deficiency
  4. too much sugar
  5. silicon deficiency

Bioavailable sources of sulfur in the diet are:

  1. MSM
  2. sulfur containing amino acids
  3. flowers of sulfur (inorganic sulfur)
  4. sulfates
  5. Both 2. and 4.

What can cause inflammation in the horse’s body:

  1. High omega-6 fatty acids
  2. High sugar/starch intake
  3. High copper intake
  4. Both 1. and 2.
  5. None of the above

True or False.   If you feed the recommended daily amount of a balancer or fortified feed, vitamin and mineral  deficiencies or imbalances are impossible.

Deficiency of which electrolyte causes alkalosis in endurance horses:

  1. sodium
  2. potassium
  3. chloride
  4. bicarbonate
  5. calcium

Compared to hay, fresh pasture always has higher levels of:

  1. vitamin E
  2. vitamin C
  3. fructan
  4. water
  5. all of the above

The most common trace mineral deficiencies in hay are:

  1. iodine
  2. selenium
  3. copper
  4. zinc
  5. all of the above

Horses differ from humans and small animals in the way they absorb:

  1. calcium
  2. protein
  3. fats
  4. iodine
  5. chromium

Assuming an equivalent adult body weight, which of these horses has the highest protein requirements:

  1. mare in late pregnancy
  2. a 2-year-old in race training
  3. yearling
  4. mare in early lactation
  5. horse recovering from surgery

Eleanor Kellon, VMD

 

 

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The Magic of Colostrum

Foaling season is upon us and everyone realizes the lifesaving importance of mare’s colostrum in transferring disease-protecting antibodies to the new foal but colostrum does much more than this.

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For example, colostrum contains a hexasaccharide that inhibits gram negative organisms, prevents biofilm formation and can even help reverse antibiotic resistance. PRPs in colostrum are small strings of amino acids, “proline rich peptides”. Previously known as transfer factors, PRPs in mare’s milk don’t actually transfer immunity; they stimulate it. Colostrum contains a host of immune system targeting cytokines and growth factors that stimulate the bone marrow. Colostrum is also rich in fat, protein in general and has a full spectrum of vitamins and minerals.

The mare’s body is programmed to short change its  own nutrition in favor or providing adequate nutrients in the colostrum and milk but it can’t manufacture deficient nutrients out of the air. Current dietary recommendations also may not always be sufficient for highest quality milk.

It has been shown that supplementation for the last 4 weeks of pregnancy with vitamin E at 2500 IU/day (over 3X the current recommendation for late pregnancy in a 500 kg mare) resulted in higher vitamin E levels in the mares, milk and foals as well as higher antibody levels in milk and the foal’s blood.

The window of opportunity for foals to consume adequate colostrum is only about 12 hours. The colostrum provides antibodies against bacteria in the environment where the mare has been living as well as her past exposures and vaccinations. It also helps jump start the foal’s own ability to form antibodies. Colostrum is gone after 24 hours and the foal’s own immune system needs to start working.

Very young foals are capable of mounting an immune response and producing antibodies but have weaker abilities in their Th1 response. Specifically this means they have trouble identifying, targeting and destroying cells that have been invaded by organisms.  This is what makes them susceptible to infections that adults easily resist, such as Rhodoccus equi.

Recent research has found that the ability to mount these sophisticated immune responses to R. equi is greatly enhanced if the foal is vaccinated by the oral route rather than injection. It had previously also been found that antibody titers in young foals were higher when the oral route was used for vaccination.

The intestinal tract is home to an extensive network of immune system cells, the GALT (gut associated lymphoid tissue). When an infection tries to enter the body by this avenue, the local immune system cells both deal with it at that level and also send out information to the immune system throughout the body, priming it to defend against the infection.

It is well known that the immune system of the GALT is also stimulated by substances that do not cause active infections. With the knowledge that foals respond best to immune challenges through the intestinal tract, this becomes an easy and appealing way to efficiently promote normal immunity in the young foal.

Even though foals lose the ability to absorb large antibody molecules (immunoglobins) in less than a day, colostrum and milk retain many immunity promoting and supporting ingredients such as growth factors, L-glutamine and Lactoferrin. Colostrum and bioactive Whey Protein are concentrated sources. Probiotic bacteria and plant components such as Mannanoligosaccharides, Arabinogalactan and Fructooligosaccharides (FOS) naturally promote a robust immune response. Vitamins B5, B1 and B12 support the high metabolic activity of immune system cells.

Combating the infectious challenges of the world is a formidable task for young foals, with the first few weeks of life being the most dangerous. You can maximize the foal’s chance of thriving by supporting high quality colostrum and making sure the foal ingests it in that critical window of the first 12 hours after birth. Beyond that, gentle support of the immune system via the oral route shows the most promise as an effective strategy.

Eleanor Kellon, VMD

 

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What is Insulin Dysregulation?

Insulin dysregulation [ID] is a term coined in a 2014 publication to describe horses with abnormal levels of insulin.  Elevated insulin used to be considered to mean a horse is insulin resistant, and in many cases it still does, but there is emerging information there can be other mechanisms behind an elevated insulin.

“Insulin resistance” means the insulin responsive cells (muscle, fat, liver) do not respond normally to stimulation by insulin. As a result, the pancreas puts out higher levels of insulin until the glucose blood levels normalize.  This is one explanation for why blood insulin levels would be higher than normal.

The level of insulin in a horse’s blood is a function of both how much is being secreted by the pancreas and the rate with which the liver, kidney and muscle clear it from the blood.  There is some evidence to suggest there may be decreased clearance of insulin in horses with high insulin levels.  However, abnormal clearance as a primary cause contributing to high insulin blood levels has not been definitively proven.

In horses that are insulin resistant, failure of the muscle and fat to respond appropriately to usual levels of insulin stimulates the pancreas to keep putting out insulin in higher amounts until blood sugar levels normalize. However, the pancreas reacts to other things besides blood glucose levels.

When the horse eats, hormones called incretins are released into the blood by the intestinal tract. Two of these incretins, GLP-1 and GIP, cause release of insulin from the pancreas.  It has been found that some ponies that test negative for insulin resistance with intravenous testing will have positive tests for hyperinsulinemia (high blood insulin) after being challenged orally with grain or dextrose.  The abnormally high insulins after feeding have been linked to higher levels of active GLP-1 incretin.  On the other hand, a similar study in full size horses with EMS (equine metabolic syndrome) did not find any significant connection between higher active GLP-1 and high insulins.

Because high blood insulin after eating or oral dextrose dosing does not necessarily mean the animal will test positive for insulin resistance by intravenous testing, the term “insulin dysregulation” was suggested to describe all horses with hyperinsulinemia, regardless of the cause(s).

Personally, I don’t think this is a good term. Dysregulation implies there is something abnormal going on.  A 2015 study by deLaat et al found that the non-IR ponies with high insulins on oral testing were also absorbing increased amounts of glucose. In that scenario, the higher levels of GLP-1 and insulin could be considered an appropriate response to the higher glucose, not “dysregulation”. The dysregulation in that case involves glucose absorption, not the reaction to it.

Similarly, if reduced insulin clearance is proven in horses with high blood insulins, it is not necessarily a “dysregulation”.  There may simply be a limit to how fast insulin clearance can occur. Alternatively, it may be entirely normal for insulin clearance to slow down when there is a situation of high glucose.

To put it another way, if insulin levels were truly being abnormally regulated it would show up in the blood glucose. Too much insulin would cause low blood sugar and too little would result in high levels. We don’t see that.

It’s important to understand that having high insulin does not necessarily mean there is insulin resistance, if only so that you do not become confused by seeing the term insulin dysregulation.  However, the bottom line for the horse is the same. High insulin is a risk factor for laminitis and the best way to combat it is with an appropriate diet and plenty of exercise – regardless of what is causing it.

Eleanor Kellon, VMD

 

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Get Ready for Allergy Season

The groundhog was right about six more weeks of winter, but spring is just around the corner and with it all the plants, molds and insects that can spell allergy.

Studies in several species and different equine breeds have uncovered a genetic predisposition to develop allergies and even the involved genes but destiny does not have to be ruled by genes.

Allergy can be described as an unbalanced or exaggerated immune response to a normally encountered challenge. The body will be reacting to a specific protein, called the allergen, in pollen, mold or insect saliva. Seasonal allergies can involve the skin, eyes or respiratory tract with all the familiar signs. Allergy is even behind some cases of seasonal headshaking.

Multiple drugs are available to treat allergy signs, and very effective when needed but the most effective, corticosteroids, come with the risk of significant side effects. There is also much you can do nutritionally to support the immune system’s ability to function in a healthful way.

A balanced diet is the first step because the minerals most likely to be deficient or negatively affected by imbalances are also those involved in homeostatic inflammatory pathways (magnesium, iodine) or have considerable antioxidant functions (copper, zinc, selenium).  Horses not on pasture have low levels of vitamin C and vitamin E as well as the critical omega-3 fatty acids which the immune system needs to maintain homeostasis. These nutrients put a strong foundation under the immune system, giving it the tools it needs to function properly.

When more support is needed there are many ways to boost the antioxidant  capacity of the body including supplemental glutamine, N-acetyl cysteine, MSM, bioflavonoids (e.g. quercetin), Turmeric, Ginger root, Green Tea, White Pine extract, alpha-lipoic acid, Grape Seed and Skin meal, Gingko biloba, Boswellia and Jiaogulan.  Gentle immune system support in the form of both pre and probiotics is indicated. Spirulina may be particularly useful as it supports the body’s normal beneficial antibody activity versus the antibodies of allergy.

Manifestations of skin allergy can be particularly distressing for your horse – or dog for that matter. These temporary irritations can be soothed by topical use of Aloe Vera, Chickweed, Chamomile, Calendula, Thyme, Arnica, Elderberry, Comfrey and White Willow bark.

For best results, start your seasonal allergy support program at least 30 days in advance of allergy season.  This gives your horse’s body the best chance of functioning at its smoothest.

Eleanor Kellon, VMD

 

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