Joint Care – The Basics

Simply because of their sheer size/mass, the joints of a horse bear a tremendous load. Since force = mass x acceleration, the load on joints only increases with exercise. 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 support supplements. The place to start is with the core ingredients described below.

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.

Target starting doses, especially for active horses are:

  • Glucosamine 8000 to 10,000 mg
  • Chrondroitin 2500 mg
  • Hyaluronic acid 50 to 100 mg

Methylsulfonylmethane (MSM) may assist in maintaining a balance between cytokines involved in breakdown, remodeling and repair.

Maintaining healthy joints is a challenge for any horse. Supplying basic support ingredients is a smart move.

Eleanor Kellon, VMD

Posted in Equine Nutrition | Tagged , , , , , , , , | Leave a comment

Fiber is Much More than Bulk

We humans are just starting to recognize dietary fiber benefits for ourselves in terms of preventing colon cancer, modulating blood glucose levels and supporting good bowel function.  In horses, there is even more to it.  Fiber is also a major and important source of energy/calories.


Humans and animals, including the horse, cannot digest fiber because they do not produce the enzymes needed to digest it down to more simple compounds that can be absorbed and used by their bodies.  However, microorganisms in their intestinal tracts can break it down by fermentation.  Because the horse has a large hind gut where food spends several days they can efficiently use fiber as an energy source.

Not all fiber is created equal. For the purpose of this discussion, I will focus on fiber types found in hay.  Lignin is a very rigid and strong fiber, found in high amounts in wood and increasing with time as grasses age.  Straws are also high in lignin. It is the most resistant to the fermentation efforts of intestinal organisms.

Next in line are cellulose and hemicellulose, also strong structural fibers but easier to ferment.  All three are classified as insoluble fibers because they do not dissolve in water.  Residual unfermented insoluble fiber gives manure much of its bulk.

On the other hand, soluble fiber which does dissolve in water is very easily and quickly fermented.  This groups includes fructooligosaccharides of various sizes including fructans, as well as pectin and beta-glucan. A large proportion of the calories present in hays come from this class of fiber.

Fiber is an important prebiotic because it feeds the beneficial organisms in the intestinal tract and stimulates gut-associated immune tissue. Insoluble fiber also works to keep organisms in the intestine, not flushed out, by providing microscopic rafts where bacteria can establish colonies.  In humans, adding fiber to a meal can reduce the glucose and insulin spikes but research has not shown a similar effect in horses.

As natural and beneficial as fiber is in the diet, some horses may react to high levels with diarrhea, particularly as they age.  If a hay analysis is available, this usually correlates with an acid detergent fiber (ADF) level in high 30s or higher, neutral detergent fiber (NDF) high 50s or higher.  The hays will be stemmy and stiff.

The solution is to find a younger, softer cut of hay. You could also try a supplement with cellulase and hemicellulase activity, fed in a small amount of beet pulp as a prebiotic. Beet pulp is rich in soluble fiber.

The fiber in your horse’s diet is much more than just roughage.

Eleanor Kellon, VMD

Posted in Equine Nutrition | Tagged , , , , , , , | Leave a comment

Metabolic Disease Misinformation

Spring grass season makes attention turn to equine metabolic disorders but there is a wealth of misinformation out there, despite solid research that disproves some pieces of advice and a clear lack of supporting research for others.

False:  NSC and fructan determine the laminitis risk of pasture/hay/feed for metabolic horses.

True: Abnormally high insulin is the risk factor for laminitis. Only simple sugars and starch can cause insulin elevations. These are measured by ESC (sugars) and starch. Fructan is not a sugar, does not elevate insulin. NSC (nonstructral carbohydrate) = ESC + starch + fructans and overestimates risk. Look at ESC + starch only and keep these below 10% total.

False: It is more dangerous to allow grazing by overweight horses than normal weight horses.

True: Laminitis risk is directly linked to insulin level, which is not tied to weight.

False: Equine Metabolic Syndrome predisposes a horse to develop Cushing’s Disease (PPID).

True:  There is no solid evidence that EMS predisposes to PPID. However, horses with EMS may be more likely to be diagnosed because PPID exacerbates high insulin levels and laminitis risk.

False:  High fat feeding is safe for horses with elevated insulin.

True:  High fat feeding causes or worsens insulin resistance in all other species where it has been tested. The safety in horses has never been evaluated.

False:  Protein supplementation will decrease the need  for pergolide in horses with PPID.

True:  Only drugs which replace the action of dopamine (dopaminergics), like pergolide, can treat PPID. Feeding more protein will not substitute for pergolide and will not help with the muscle loss associated with uncontrolled PPID.

False: Herbal supplements and acupuncture can reset pituitary function.

True:  These are baseless claims.

False: Horses not responding adequately to low dose Prascend  for PPID should have cyproheptadine treatment added.

True:  It was shown almost two decades ago that cyproheptadine does not help control PPID.  There has been no new evidence since then.

False:  Obesity, metabolic syndrome and laminitis are inflammatory conditions.

True: While this might seem to make sense, and is true in humans and lab animals, formal research does not support a significant inflammatory component in horses.

False: Only dynamic testing, like glucose challenge or insulin response tests, can accurately diagnose EMS.

True: Horses which test positive with abnormal baseline insulin testing and proxies based on insulin and glucose do not need to be confirmed by dynamic testing. The problem with false negative results on baseline insulin and glucose testing is that the ranges for normal are too high. Field testing published 14 years ago showed upper limit of normal for horses on pasture is 12 uIU/mL and recently published research, validated by intravenous insulin sensitivity testing, established that the upper limit of normal for fasting insulin should be 5.2 uIU/mL. Laboratory “reference ranges” are not the same thing as normal.

Don’t believe everything you read or are told.  For up to date information from an independent source whose sole focus for two decades has been the dissemination of  accurate, science-based information on metabolic disorders in horses visit and download the free NO Laminitis! conference proceedings.

Eleanor Kellon, VMD

Posted in Equine Nutrition | Tagged , , , , , , , | Leave a comment

Vitamin E and Selenium Work Together

Vitamin E and selenium are nutrients familiar to most horsepeople.  They are among the most common deficiencies in unsupplemented animals – and also the only two where deficiency diseases are still routinely seen.  Suboptimal levels also impact health and performance at intakes higher than those that will trigger full blown deficiency syndromes.

Vitamin E and selenium are powerful protectors of muscle as well as immune function.

E and Se are often supplemented together but contrary to popular belief they do not actually work together, nor is their absorption from the intestinal tract interrelated in any way. However, they complement each other to provide broad spectrum protection to the body’s cells.

E and Se are both important antioxidants. E works to prevent fats within membranes from oxidative damage.  Se, as part of the glutathione peroxidase enzymes, works to protect the internal watery portions of cells from free radical injury. Free radicals are a by-product of cells generating energy for work or cell division and of immune system activity.

Vitamin E and selenium status is documented to significantly impact:

  •  The nervous system
  • Muscular function
  • Fertility/sperm quality
  • Antibody levels in colostrum
  • Immune function
  • Red blood cell integrity in exercising horses
  • Heart health

Selenium is also integral to the enzyme which converts the inactive form of thyroid hormone (T4) to the active T3.

In most areas of the US and Canada, selenium is barely adequate to frankly deficient.  Horses not being maintained on pasture have extremely low levels of vitamin E in unsupplemented diets. E added to feeds or multi-ingredient supplements often acts more like a natural preservative than a supplement because even stabilized forms of the vitamin can break down easily.

Horses absorb inorganic selenium (e.g. sodium selenate) well but absorption of this form may be reduced by high levels of competing minerals in the diet. For this reason, some or all of the selenium supplement should be in the form of high selenium yeast.

Because E is a fat soluble vitamin it is best given dissolved in fat.  If your supplement is dry,  mix it into some oil or sprinkle it on top of oil top dressed on the feed.

E and  selenium are two of the most important and the most often deficient nutrients in the horse’s diet.  Make sure your horse’s intake is adequate.

Eleanor Kellon, VMD

Posted in Equine Nutrition | 2 Comments

COVID-19 Stress and your Dog

It’s certainly true that dogs can pick up on their owners’ stress and anxiety. Research has shown that dogs’ cortisol levels will even rise in concert with their owners’.

Simply having everyone home is your dog’s first clue that something is different. If you are also stressed out about the pandemic and how it may touch your life, they will pick up on that too. However, the dog’s first priority is simply being with you. If sensing your anxiety they will likely do what they do best – stay close, follow you around, even press up against your legs.

To your dog, when they feel something is wrong, being with you is the solution. If anxiety in the household is high, your dog may feel a little uncertain and be less spontaneous than usual but a pat or word from you will be all it takes to trigger a big doggie smile and get that tail wagging.

The biggest toll on your dog is actually most likely to come when your stay-at-home orders are lifted. Your pup will have been accustomed to having your family around all the time and losing that could trigger anxiety behaviors like barking, destroying things in the home or soiling.

To help minimize the blow, try things like making sure your dog spends some time alone in the yard when you are home, or home alone when you have to go out for essential errands. If acclimated to a crate, crate your dog for periods when you are home.

If your pet does develop signs of separation anxiety when your life returns to normal, review the suggestions in this article from the ASPCA

Eleanor Kellon, VMD

Posted in Equine Nutrition | Tagged , , | 1 Comment

Feeding Lactating Mares

No sex, no age group, no pregnancy stage, no use or activity level has higher nutritional requirements than a lactating mare.  The lactating mare is still eating for two but without her foal having direct access to nutrients from her blood.  Her rapidly growing foal is larger by the day. She must take in sufficient nutrients to produce the milk for him to flourish.

In peak lactation the mare needs 1.8 times more calories than when she is not milking. That’s the easy part. She also needs 2.5 times more protein and 3 times more lysine, calcium and phosphorus.  If her diet was only providing enough protein, lysine and minerals to support her adult, nonpregnant body condition, simply feeding enough to meet calorie needs is going to leave sizeable deficits in protein/lysine, calcium and phosphorus. Even diets adjusted for late pregnancy will not have a sufficient concentration of protein, lysine and minerals.

Survival of the species gives precedence to providing for the foal. If the mare’s diet is deficient in protein she will begin to break down her own muscle tissue to obtain amino acids for the milk. This leads to both loss of muscle mass and weight loss in general.  Milk production also suffers with insufficient protein. To get the minerals she needs she will leach calcium and phosphorus from her bones, trace minerals as needed from any stores she has in the liver and kidneys. This is not a sustainable situation for her future health and fertility.

What she needs will, as always, depend on what is in the base diet. If the mare is turned out on sufficient high quality young pasture, calories, protein, lysine, vitamin and essential fatty acid requirements will be met.  The only hole will be minerals. Working with a professional will help you be more precise but generally these mares do very well with a carrier feeding of 1 lb each alfalfa pellets and plain oats with 1.5 to 2 times the regular dose of a  vitamin/mineral supplement with a calcium:phosphorus ratio of 1.2:1.

If the mare is on hay with a protein level of at least 11%, her crude protein needs will be met but she will need mineral supplementation as above plus key amino acids of lysine, methionine and threonine, double the usual dose of 10-5-2 grams per day.  Mares not on fresh pasture also need vitamin E and essential fatty acids from flax or chia.

If the hay is below 11% protein, substitute up to 2 pounds of a 25% protein vitamin and mineral supplement for the minerals above. If this still isn’t enough to make up the protein deficit, add a 40% protein supplement to avoid excess minerals or too much bulk.  Decrease the triple essential amino acid supplement to one dose and finish off with the vitamin E and flax.

One more thing extremely important for lactating mares is salt. Add 2 oz directly to food or sprayed on hay and keep loose salt available in a small feeder. This will help ensure sufficient drinking to cover the fluid requirements of milk.

As the foal grows and eats more solid food, milk production will drop and you will see the mare start to gain weight. When this happens, begin decreasing how much she is fed and cut back on all supplements by the same percentage – e.g. 10% drop in food and 10% drop in supplements.

You can get away with a lot when feeding lactating mares but the rewards of doing it correctly are immediately obvious in the vigor, condition and health of both the mare and her foal.

Eleanor Kellon, VMD

Posted in Equine Nutrition | 2 Comments

Spring Pastures

In most areas of North America, pastures are coming to their verdant peak.  This beautiful flush is also a powerhouse of nutrition for the horse.

Spring grass has abundant supplies of  vitamins and omega-3 essential fats which likely contribute to the undeniable bloom and gleam of horses on young pastures.  They often top 20% protein in the early growth stages. Fiber levels are low; calories and digestibility at their peaks.

With feral horses coming out of winter in poor condition, foals on the way, spring grass growth is literally life-saving. There are many differences between that scenario and today’s typical domesticated horse.

Natural prairies, steppes and savannas are different from well maintained pastures. Their grasses also have superior nutrition in the spring but pastures for domestic animals are seeded and fertilized so the growth is much more dense. The feral horse must travel a lot further (exercise!) to get the same amount of grass. The domestic pastures are also typically “improved” strains of grasses that will withstand a lot of traffic, grazing and weather extremes. Improved grasses have higher simple sugar levels.

Access to spring pasture leads to weight gain for any horse that does not have high calorie requirements, like the lactating mares and growing foals.  It also is a drastic diet change from hay, often resulting in soft manure or even bloating and abdominal discomfort. Gradual introduction to spring pasture, supplemental psyllium to increase fiber and a high potency probiotic can help the digestive tract adapt to the diet change.

The most well known potential danger of spring pastures is deterioration of the hooves.  While it has been claimed that any horse may develop pasture-related problems, the research does not support this.  Study after study over the last decade and a half, including over multiple year periods, has found that high insulin levels are the risk factor.

Ironically, many breeds that remain true to their ancestral feral form, like Shetlands and Icelandics, are among the most at risk. However, in their natural habitat grass was neither abundant nor the sugar-loaded variety available to domesticated horses.

The only sure way to protect horses at risk is to keep them off pasture, especially in the spring, or use a completely sealed muzzle. If you play with fire and lose, immediately take the horse off pasture and feed  only hay known to be less than 10% sugar and starch combined or soaked hay (soaking lowers sugars).  The safest carrier for supplements is a small amount of beet pulp which has been rinsed, soaked and rinsed again to remove excess sugar or molasses.  Hoof trim should be done according to radiographs.

The horse is otherwise best supported by ingredients which are directed to nitric oxide production. . The herb Gynostemma pentaphyllum (Jiaogulan) is a powerful stimulant for nitric oxide production. This is helped by providing the precursors for nitric oxide in the form of L-arginine and L-citrulline. Antioxidants also combat oxidative stress which inhibits the activity of the enzyme that produces the beneficial nitric oxide inside blood  vessels [eNOS – endothelial nitric oxide synthesis].

Spring grass is nature’s most powerful tonic but there can be too much of a good thing. Utilize it wisely.

Eleanor M Kellon, VMD

Posted in Equine Nutrition | Tagged , , , , , , , , , , , , , | 7 Comments

Tendon Care

We focus a lot of attention on our horse’s moving parts, the bones and joints which bear weight and absorb impact, the muscles which generate movement. Equally important are tendons and ligaments.

Tendons originate in muscles and terminate on bone. When muscles contract they shorten and pull on their attached tendons, focusing the force of the muscle action.  Ligaments on the other hand are the major stabilizers. They attach bone to bone, within or across joints. Ligaments serve to keep bones in the correct alignment for bearing weight and restrict excessive movement.

Sensible conditioning schedules, meticulous hoof balancing and careful attention to nutritional needs are the most important things we can do to maintain tendon and ligament health.  This is especially important because their are several common deficiencies which can impact it.

Both muscles and tendons/ligaments are made of protein but with a very different structure. Tendons and ligaments are connective tissues where the major protein is collagen.  Collagen protein has a unique amino acid composition.

The most abundant amino acid in collagen is glycine, which is nonessential meaning the body is able to manufacture it. However, glycine synthesis is not always adequate to support connective tissue needs. The most  common essential amino acid in collagen is lysine; essential meaning it must come from the diet. Lysine is also the most commonly deficient amino acid in equine diets. Hydroxylysine, which is found only in connective tissue, is also made from lysine.

The amino acid supply is only the start of the process for healthy tendons and ligaments. The trace mineral copper is required for the production of hydroxylysine and also the creation of reinforcing cross-links between collagen  strands. Like lysine, copper is another nutrient which is often deficient in our horses’ diets.

Also commonly deficient is zinc, which is important to the integrity of the insertion sites of tendons and ligaments on bone, as well as for the antioxidant enzyme superoxide dismutase.

As with all tissues, the horse’s body must deal with inevitable exercise-related wear and tear to tendons and ligaments. Research has shown that nitric oxide is a key element in tendon and ligament maintenance.  The herb Gynostemma pentaphyllum, aka Jiaogulan, provides powerful support of nitric oxide generation from the healthful eNOS enzyme system while assisting the horse in the homeostatic regulation of the inflammatory iNOS enzyme.

Tendon and ligament health is critical to keeping your horse moving freely. Stress is largely beyond our control, but nutrition is not.  Targeted supplementation can offer powerful support.

Eleanor Kellon, VMD

Posted in Equine Nutrition | Tagged , , , , , , , , | Leave a comment

Spring Sneezes, Coughs and Itchies

Any horse will itch from a mosquito bite and sneeze, snort or cough from an inhaled irritant but some individuals suffer from exaggerated reactions.

Seasonal plant and insect irritants cause distress in some horses

Both normal reactions and seasonal allergies originate in the immune system. The immune system must react to and process countless exposures.  The horse is not even aware of most of them.

Temporary common irritations, like itching from insect bites, originate in the “primitive” or innate immune system which functions on a shoot first, ask questions later, philosophy and generates many irritating substances like free radicals and histamine. The sophisticated arm of the immune system does ask questions, determines the correct type of antibody or detoxification response and also maintains homeostasis by regulating and terminating all immune reactions as appropriate.

We can help horses with seasonal hypersensitivities by providing the immune system with substances which support normal function. These include:

  • Antioxidant supplies from vitamin C, MSM, bioflavonoids, beta-carotene, lipoic acid, grape seed and skin plus other bright berries, N-acetyl-cysteine
  • Turmeric, Ginger, Garlic, Flaxseed and Boswellia to support normal homeostasis during inflammatory reactions
  • Jiaogulan to help maintain balance in nitric oxide generating enzyme pathways and also support normal airway dilation
  • Spirulina for maintenance of histamine at normal levels and support of correctly balanced antibody production by the immune system

The goal of this type of supplementation is not to block any reactions but rather to work with the immune system’s built in mechanisms for achieving balance.

It takes time for this approach to work. If you start when the seasonal issues are already under way the results will not be as good as gearing up for the season by beginning supplementation 4 to 6 weeks in advance. Otherwise, it’s the proverbial shutting the barn door after the horse has escaped scenario.

The physiology of both normal immune system function and exaggerated reactions is complicated but we have several weapons at our disposal for helping to maintain normal function. Just be sure to start early.

Eleanor Kellon, VMD

Posted in Equine Nutrition | 10 Comments

How Hard is Your Horse Working?

When you read articles about feeding your horse for their level of work you will often see reference to light,  moderate, heavy and extra heavy. What exactly does that mean?

In the 6th revised edition of “The Nutrient Requirements of Horses” (NRC, 2007), there are four categories for exercising horses: light exercise, moderate exercise, heavy exercise and very heavy exercise.

Light exercise is described as 1 to 3 hours/week of mostly walking and trotting. Many horses kept for recreational riding would be included in the light exercise category. 20.0 Mcal/day for a 500 kg horse. (Mcal = megacalorie)

Moderate exercise consists of 3 to 5 hours/week of mostly trotting with some walking, some cantering and possibly some jumping or other type of more difficult activity. Horses used for horse shows, ranch work and frequent recreational riding would fit into the moderate exercise category. 23.3 Mcal/day for a 500 kg horse.

Heavy exercise is described as 4 to 5 hours/week of trotting, cantering, galloping and some jumping, cattle work, etc. Horses engaged in three day eventing, polo, endurance racing or other competitive events would be in this category. 26.6 Mcal/day for a 500 kg horse.

The very heavy exercise category includes racehorses and a few other horses that compete at the elite level of endurance or three day eventing. 34.5 Mcal/day for a 500 kg horse.

Note: 1 kg = 2.2 lb. 1 kg of good quality grass hay averages 1.9 Mcal.  1 kg of commercial sweet feed or pellets contains about 4.7 Mcal; more if heavily fat fortified.

These are just a rule of thumb and can be influenced by several factors such as:

  • Fitness. An unfit horse will work much harder to perform even light exercise.
  • Horse’s body condition. Likewise, an overweight horse must work harder than average at the same exercise level.
  • Rider and tack weight. The more the horse is carrying, the harder they have to work.
  • Terrain.  Horses working on hills, uneven ground or deep footing will work harder to perform the same work as they would on flat, level surfaces.
  • Metabolism.  Easy keeper types at maintenance tend to also need fewer calories when working.

Ultimately, the best determinant of whether the horse is being fed correctly is his body condition score. . Even  though you may have to modify the “average” recommendations, they are a good starting point.

Eleanor Kellon, VMD


Posted in Equine Nutrition | 1 Comment