Researchers: Young Foals in Halter Training Need Frequent Days Off

Biting is a sign of stress in foals. In this study, foals less than 8 weeks old that didn’t have training breaks bit their handlers more frequently than ones that got days off between training sessions.

Researchers: Young Foals in Halter Training Need Frequent Days Off
He’s just a baby, but he can still learn important tasks like leading. According to Australian and New Zealand researchers, though, he’ll need a day off about every two or three days.“We were really surprised to see such a significant difference in the amount of biting these young foals did according to how often they got days off,” said Hayley Randle, PhD, of Charles Sturt University’s School of Animal and Veterinary Science, in Wagga Wagga, New South Wales, Australia.

“Biting in young foals is a behavioral sign of stress,” she explained. “These foals were only training less than half an hour a day, but by the fourth day in a row many were biting the handlers, some frequently. Meanwhile, foals of the same age that got a one-day break after the second training day were much less likely to bite, even on the fourth day of actual training.”

Randle presented the work of her colleague, Jaymie Loy, BSc, of Charles Sturt University, during the 15th annual International Society for Equitation Science (ISES) conference, held Aug. 19-21 in Guelph, Ontario, Canada. The team worked with foal trainers in New Zealand who practice evidence-based foundation training using negative reinforcement.

The group trained 20 Thoroughbred foals to move forward and stop in response to halter pressure. All the young horses worked for a total of six or seven days, for up to 25 minutes each day, depending on their progress during each session. However, half the foals had one-day breaks between two days of training (Days 3 and 6), whereas the other half had a single, two-day break after the first four days in a row of training.

The researchers found that regardless of the schedule, all foals learned at about the same rate and had the same level of recall of what they’d learned before, Randle said. Where the researchers saw a difference, though, was in the youngest foals’ behavior. Specifically, foals under 8 weeks of age showed a remarkable increase in biting during the fourth consecutive day of training.

“If we want to establish a positive horse-human relationship from the start, we need to be considering the cognitive abilities and the limitations when working with young horses and handle them appropriately,” Loy said in a subsequent interview. “The foals in our study that were younger than 8 weeks of age clearly showed signs of stress, as seen through the biting, by having several days of training in a row.”

Study foals that were older than 8 weeks did not show an increase in biting behavior, even on the fourth consecutive day of training, she added. It seemed to be a phenomenon of younger foals in this small study population, she said.

“We recommend planning a day off within the first four days of training young foals in order to decrease potential stress-related behaviors,” said Randle.

About The Author


Christa Lesté-Lasserre is a freelance writer based in France. A native of Dallas, Texas, Lesté-Lasserre grew up riding Quarter Horses, Appaloosas, and Shetland Ponies. She holds a master’s degree in English, specializing in creative writing, from the University of Mississippi in Oxford and earned a bachelor’s in journalism and creative writing with a minor in sciences from Baylor University in Waco, Texas. She currently keeps her two Trakehners at home near Paris. Follow Lesté-Lasserre on Twitter @christalestelas.

Footing Surfaces and Loading on Equine Legs

Canadian researchers shared the results of their footing and force studies at an international conference. One looked at limb loading force, while the other investigated the impact of footing firmness and horse size.

Footing Surfaces and Loading on Equine Legs
Despite investigations, racehorses continue to break down on the tracks, suffering catastrophic injuries leading to euthanasia. Meanwhile, in the sport horse world, soft tissue injuries continue to cut performance careers short. As more industry members raise questions about how ground surface quality affects safety, scientists are digging deeper into footing science.“Numerous variables affect the interaction between the hoof and the ground surface, and any of these variables could contribute to an increased risk of injury in horses,” said Alexis Szpakowski, a recent bachelor of science graduate from the University of Guelph, in Ontario, Canada.

Those variables include not only the footing’s qualities but also the horse’s weight, the direction he’s going (straight or on a curve), the direction of turn, the lead he’s on, and multiple other factors, according to Szpakowski and her colleague Danielle Halucha, a master of science candidate also at the University of Guelph. Both scientists presented their work in separate presentations during the 15th annual conference of the International Society for Equitation Science (ISES), held Aug. 19-21, 2019, in Guelph.

When a hoof hits the ground, it doesn’t just touch and go, the researchers explained. It has an initial impact that causes the hoof to brake and experience internal vibrations that can extend up the limb. The hoof slides briefly before reaching a full stop with the horse’s mass centered over it. In a gallop, the horse’s entire body weight, multiplied in force due to the combination with speed, bears down fully on a single hoof during this midstance, which includes a push-off to propel the entire horse forward. As the body mass passes in front of the limb, the hoof rolls forward and over the tip in what’s known as the “breakover,” before lifting off the surface.

“In each of these phases, the hoof experiences different forces and accelerations, and each of them is associated with different risk factors for injury,” said Halucha.

It’s very difficult to identify the mechanical causes of injury, however, she added. With so many factors involved, concerning both the horse and the environment (surface and conditions), recognizing the links between injuries and the many forces affecting the various phases of contact between hoof and surface is a daunting task.

“We know that racehorses experience major force on their limbs, reaching 2.5 times their body weight on a single hoof during certain phases of stance at the gallop,” Halucha said. “In my study we saw that strain can vary considerably from one limb to the other, depending on which lead the horse is on and if he’s galloping on a straight line or a curve.”

As for Szpakowski, she said she found lower limb forces in a soft sand arena than a hard-packed sand arena—with the exception of heavier horses. Bigger horses actually had higher midstance forces in soft sand than hard-packed sand.

“We saw that both size and surface affect loading at all phases of the stance,” she said. “These factors work independently and in combination to cause changes in the limb loading, with the most obvious finding in my study being that heavier horses experience greater forces on soft sand at midstance whereas, for the lighter horses, the harder sand creates this effect.”

In each of the two studies, the scientists used accelerometers and strain gauges attached to the front hooves of working horses. Szpakowski compared measurements between 10 horses ridden at a trot under the same rider in two conditions: a soft sand outdoor arena and a hard sand indoor arena. She recruited horses of varying breeds and weights, ranging from 356 kilograms (783 pounds) to 673 kilograms (1,480 pounds). Meanwhile, Halucha looked at 10 Thoroughbreds (2- and 3-year-olds and one 10-year-old) galloping a lap on a dirt track.

“Loading definitely differs between left and right limbs depending on the curve as well as the lead,” Halucha explained. “We went into the study expecting to find a significant effect of curve, which we did, but we also found one for (front) lead (leg). This needs to be kept in mind when making the suggestion that a horse just ‘took a bad step.’ There’s clearly more to it than that.”

More detailed analysis revealed that the younger horses tended to switch leads frequently, whereas the 10-year-old horse did not, she added.

While the studies were preliminary and could not lead to specific guidelines, they helped “contribute to the growing body of knowledge” about footing and injury risk, said Szpakowski.

“Our findings showed hoof-surface mechanical interactions that aren’t immediately intuitive, and being aware of this could be a key factor in injury prevention,” she said.


Christa Lesté-Lasserre is a freelance writer based in France. A native of Dallas, Texas, Lesté-Lasserre grew up riding Quarter Horses, Appaloosas, and Shetland Ponies. She holds a master’s degree in English, specializing in creative writing, from the University of Mississippi in Oxford and earned a bachelor’s in journalism and creative writing with a minor in sciences from Baylor University in Waco, Texas. She currently keeps her two Trakehners at home near Paris. Follow Lesté-Lasserre on Twitter @christalestelas.

Winterizing Horses

Take a few simple precautions and management approaches to help your horse weather winter safely.

Winterizing Horses

Take a few simple precautions and management approaches to help your horse weather winter safely.

Looking out upon a wintry farmscape it’s common to see equine forms silhouetted against the snow, huddled against the wind. Or, you might glimpse the glow of lights from a barn housing blanketed equine charges. In northern climes winter generally is a time of slowed activity for both horse and rider, but attentiveness to horses’ health and management is just as crucial during these chilly months as it is during the warmer ones.

How should you prepare your horse so he will thrive in winter and emerge from it in robust condition, ready for a busy riding season? Let’s look at some steps you can take to protect your horse’s body systems.

Protect and Support Respiratory Health

Horses evolved as plains animals, well-equipped to deal with wind, cold, and snow. Nonetheless, horse owners like to protect their charges from the elements, often building complex stabling structures to keep them sheltered and warm.

“When horse function was equivalent to automobiles, we put them in the barn at night after being out all day plowing fields, transporting people, pulling wagons,” says Eileen Fabian Wheeler, PhD, professor of Agricultural Engineering at Pennsylvania State University. “Now the situation is the opposite: Many want to keep their horses in the stable 23 hours a day with one hour a day in work. It seems we have lost perspective on the purpose of a horse stable.”

One of the downsides to stabling around the clock in winter stems from poorly ventilated structures: “Closing a stable up tightly traps stale air pollution inside with accumulation of urine ammonia, endotoxin particulates from manure, dust, and molds from hay and bedding–these pollutants challenge the equine respiratory system,” says Wheeler.

So if you plan to keep your horses stabled this winter, keep in mind that inhaled ammonia can destroy their airways’ epithelial lining and contribute to the development of respiratory diseases such as inflammatory airway disease (IAD) or recurrent airway obstruction (heaves), says Wes Elford, DVM, an equine practitioner from Randolph, Wisconsin.

First determine whether your barn’s ammonia levels are high, and then take steps to improve air quality. Wheeler recommends smelling the air as you enter the stable: “Ideally, you’ll enjoy a light essence of hay and horse rather than wrinkling your nose at a pungent urine odor,” she says. “If you smell ammonia, then it’s already too high. While it’s desirable to keep ammonia levels less than 10 ppm, the human nose won’t detect its odor until at least 20 ppm.”

She further stresses the importance of considering a horse’s usual breathing zone when assessing air quality; respiratory pollutants are greatest at foot level and especially in stalls. “It is not uncommon for the working aisle of a stable to have much better air quality than the stalls,” she says.

You might be inclined to don five layers of clothing and want to seal up the barn for warmth, but Wheeler notes that “even during the worst winter days, cold, dry fresh air is desirable and comfortable for horses. While horses’ body heat warms air in a closed barn, unfortunately humidity, which is also trapped, makes the barn damp, dank, and feeling colder.”

Elford acknowledges the difficulty in keeping barns open in inclement weather: “While we need to keep water pipes and waterers from freezing, a complete exchange of air is necessary for ­sufficient ­removal of air pollutants. Heating waterers and burying pipes protects from ­freezing.”

Barn air quality benefits from ventilation year-round, via small slots or openings along the building’s perimeter that ­allow fresh air to enter and stale air to leave. Opening doors and windows further amplifies air circulation for improved respiratory health.

Horse traffic and footing maintenance in indoor arenas introduce dust to adjacent stalls. During winter Wheeler suggests oiling footing with high-grade, Vaseline-based petroleum (not motor oil) to weigh down and glue particles together so they don’t loft. “Watering the footing,” she says, “increases the likelihood of it freezing into hard lumps, which is dangerous for riding. This also increases humidity in the building, which impacts structural soundness by rusting metal and rotting wood.”

Another means of reducing harmful particulate dust levels is to store hay and bedding in a separate structure. This decreases environmental dust from horse and people activity, especially during feeding time. It also eliminates the fire hazard created by combustible hay.

Wheeler adds, “Turn horses outside when cleaning stalls to decrease exposure to aerosolized particles of molds, dust and endotoxin.”

Respiratory challenges also come in the way of pathogens; immunizations against respiratory viruses (e.g., influenza, ­rhinopneumonitis, and strangles) help prevent infectious upper airway diseases in horse herds. Veterinarians recommend boostering these vaccines in both autumn and spring. Work with your veterinarian to ensure your horse’s immunizations are up-to-date prior to winter; this, along with clean, well-ventilated barns, can help prevent respiratory illness.

Outdoor Shelter

Full-time turnout (paddock and/or pasture) is the most healthful way for a horse to live, even in cold climates. “The best housing for horses in winter is no housing at all, or at most a wind break,” says Elford. Wheeler also likes using run-in sheds: “The design should provide a dry location and reduced wind speeds. Surrounding ‘sacrifice’ paddocks with an engineered surface that sheds precipitation and is easily cleaned of manure provides a safe environment where being at liberty is the goal rather than grazing.”

Heading into winter, check that your sheds are in good repair, with roofing in place, nails safely embedded in wood, and no protruding sharp edges. Ideally your run-in should offer protection from the elements from at least one direction, with the solid side facing the prevailing winter wind; a three-sided structure open to the south allows drying, says Wheeler. “A shed design works best if at least eight feet high and with exits no less than 10 feet wide to allow two horses to pass,” she says. “Consider also the location of structural support posts–horses find it difficult to transition from bright to low light levels and could clobber themselves on the posts.”

To Blanket or Not to Blanket

Unless your horse needs his coat clipped for activities such as showing or foxhunting, most veterinarians recommend letting his coat grow out naturally during winter. For horses with a full body of hair, says Elford, blanketing is not usually necessary. “Horses have an innate ability to withstand cold and wind with no more than a windbreak,” he says. Furthermore, blankets tend to compress a wooly coat’s layers, which compromises their insulating properties, notes Wheeler.

That said, “show and performance horses may need (clipping and) blanketing to control winter hair growth so they can exercise without getting too sweaty and so sweat dries easily,” Elford says. If you’ll be blanketing such a horse this winter, ensure that your blankets are clean and in one piece before the weather turns. Consider a partial rather than a full clip for the benefits of easily cleaned sweaty areas and heavy hair coat in other areas.


While turning a horse out is ideal for his general health, doing so in questionable winter footing is not always a safe bet. “It’s dangerous to turn horses out when the ground is frozen in ruts created by hoof prints or vehicular traffic–I have seen coffin bone fractures as a result of a horse stepping into a frozen rut,” says Elford. “Also, following a thaw, ‘lakes’ of (pooled) water then freeze overnight with pastures turning into ‘glare ice.’ This increases the risk of fractured legs and split pelvises.” Plan ahead to have a safe, dry area to keep horses in times like these when traction is at a minimum. Alternatively, keep some form of gravel or even kitty litter available to put onto unavoidable icy areas.

Exercise and Feet

To keep your horse in moderate fitness and ready for more intense conditioning come spring, keep him in light exercise during winter. Besides benefiting musculoskeletal and mental health, Elford remarks, “Exercise is also important to maintain intestinal motility.” Turnout and/or consistent light riding both provide exercise.

In preparing your horse’s feet for winter, Elford recommends removing shoes if the horse isn’t worked heavily. However, “if you intend to ride consistently, particularly on trails, and feel the need for shoes,” he says, “then shoeing with snow pads helps clear snow from the bottom of shod hooves–this minimizes stumbling over ice balls.”

He describes methods to increase horseshoe traction on packed snow and ice: “Drilled-in studs about 1/4 to 1/8 of an inch long or borium-tipped horseshoe nails provide grip without causing excessive, unyielding hoof grab.”

In cold weather take time for warming up and cooling down. “Walking is an effective warm-up,” says Elford. “The cool-down is hardest because once a sweaty horse stops work, he can quickly chill. Evaporation of sweat pulls heat from a horse’s internal core—this compounds the chill of winter air. A horse damp from a workout can be blanketed immediately upon pulling tack. In addition, continue walking him a short while to maintain muscle (blood) circulation; this helps avoid muscle cramping while skin and muscles cool down gradually. Once he’s dry, the blanket can be removed unless the horse has been clipped.”

And while you might feel like frigid air assaults your airways during the first few minutes of a winter run, Elford notes he has never encountered a horse with a respiratory or breathing problem caused by exercising in cold weather. A horse’s long nasal passages warm the air as it is inhaled. Toweling off frosty muzzles and other wet areas after a ride, however, helps reduce the slight risk of frostbite before turning the horse out again.

Digestive Health

Water intake is especially important in winter to maintain hydration and avoid impaction colic. “Drinking is encouraged by providing warm water through heated buckets or stock tanks with heaters,” says Elford. “Water heating systems should be grounded since horses can sense low voltages and may refuse to drink. Use PVC pipe coverings over electrical wires to prevent a horse from electrocuting ­himself.”

Prior to winter make sure you’re well-stocked with good quality hay, particularly in the event of supply shortages due to drought. “In winter a horse’s diet doesn’t need to change,” advises Elford. “We’ve been told that additional calories help to keep a horse warm but it’s best to increase calories in winter by offering more hay, not grain, as fermentation of forage in the hindgut generates internal warmth. Forage also doesn’t create a carbohydrate load in the hindgut that could cause laminitis (inflammation of the sensitive laminae that connect the hoof to the coffin bone).”

Elford recommends feeling a horse’s back, withers, and ribs routinely to track body condition and adjusting rations accordingly. Make sure your horse has a healthy fat covering over his ribs (body condition 5 or 6 out of 9) rather than entering winter months in too lean a ­condition.

In addition, good dental care maximizes the nutrition horses get from their feed. “Teeth should be checked at least yearly, particularly for the middle-aged and older horse; most horses need dental work and floating once or twice a year,” notes Elford. Completing routine work on any questionable dental issues by late autumn gives your horse the best chance of maximizing his groceries during winter months.

Attention to digestive health also includes parasite control. Veterinary recommendations in northern climes include decreasing deworming frequency during winter months; however, consult your veterinarian about using fecal egg count tests to tailor this program to your farm.

Take-Home Message

In general, horses thrive best when there is room to move around in and fresh air to breathe–regardless of the season. Movement helps keep musculoskeletal tissues limber and healthy, and it keeps the digestive tract motile and the equine respiratory tract healthy. Taking a few simple precautions in addition to these basic, healthful approaches can help your horse weather winter safely.


Nancy S. Loving, DVM, owns Loving Equine Clinic in Boulder, Colorado, and has a special interest in managing the care of sport horses. Her book, All Horse Systems Go, is a comprehensive veterinary care and conditioning resource in full color that covers all facets of horse care. She has also authored the books Go the Distance as a resource for endurance horse owners, Conformation and Performance, and First Aid for Horse and Rider in addition to many veterinary articles for both horse owner and professional audiences.

Chia or Flax: Which is Better for My Horse?

Discover the differences between these two trendy, omega-3-packed seeds that can be used to supplement equine diets.

Chia or Flax: Which is Better for My Horse
QUESTION:    I would like to see someone do a nutritional comparison between flax seed and chia seed supplementation in horses. Is one better than the other, is it a matter of preference, or do they offer the horse different benefits? — Cindy Bean, via Facebook

ANSWER:    Chia and flax are typically added to equine diets as supplemental sources of omega-3 fatty acids. Both are rich in linolenic acid (ALA), which is a precursor to the longer chain fatty acids: ecosapentaenoic acid (or EPA) and decosahexaenoic acid (or DHA). Flax or linseed meal, the end product after fat extraction, has long been used in livestock feeds as a protein source. But more recently interest has built around the whole flax seed due to its potential impact of inflammatory conditions. Equine research has shown potential benefits in improving short-term insulin sensitivity, as well as reducing sensitivity to biting fly allergy. Other benefits might exist in mediating a number of inflammatory conditions.

A 2012 study by Ciftci et al published in the European Journal of Lipid Science and Technology showed that while whole flax seeds contained more total fat than chia (about 45% vs. 35%), the difference in omega-3 fatty acid content was small, with about 58% of the total fat being ALA in flax and 60% in chia. These percentages might appear higher than you see on product labels as products may express omega-3 and -6 as a percentage of the total product rather than as a percentage of the total fat. Chia had slightly higher omega-6 fatty acid content compared to flax (20.37% vs. 15.3%), giving chia an omega-6 to 3 ratio of 0.35:1 versus 0.27:1 for flax. This ratio is significantly lower than other common sources of fat in the equine diet, such as rice bran oil (21:1), soybean oil (7:1), canola oil (2:1), and corn oil (46:1).

What does this mean in real world terms? It means that every 100 grams of flax provides approximately 45 grams of total fat, 26 grams of ALA omega-3, and 6.8 grams of omega-6, whereas 100 grams of chia provides approximately 35 grams of total fat, 21 grams of ALA omega-3, and 7 grams of omega-6. Remember that these values will vary with cultivar (a plant variety that has been produced in cultivation by selective breeding) and growing conditions. While the fatty acid composition is where much of the attention is for these two seeds, they have other potential benefits, as well.

Both seeds provide natural vitamin E as mixed tocopherols (a family of vitamin E compounds naturally found in vegetable oils, nuts, fish, and leafy green vegetables), with the majority in the form of gamma tocopherol. Flax provides more total tocopherol than chia. Vitamin E is an important nutrient in the equine diet as it is a potent antioxidant. Flax and chia are both sources of beneficial, highly digestible fiber, and flax is a rich source of lignans, a type of phytoestrogen (an estrogen occurring naturally in legumes considered beneficial in some diets). While phytoestrogens occur in many plants, they can interfere with estrogen metabolism and this has caused some owners to move away from flax in favor of chia, which has lower lignan levels.

Another plus for chia is that it does not need to be ground. While many people successfully feed flax whole, the outer shell is hard and may not be fully broken down during digestion, which inhibits the horse’s access to the nutrients within. For this reason flax is commonly fed ground. Owners either grind the seeds and feed immediately to prevent oxidation of nutrients, or buy ground stabilized flax, which has a shelf life or anywhere from six month to two years, depending on the grinding process used.

A common misconception is that you must boil flax before feeding. This is because flax contains cyanogenic glycocides, which can be released as cyanide should they come in to contact with enzymes within the seed. The reality is that it is unlikely that harmful levels of cyanide are released due to the fact that the enzymes within the seed are denatured by stomach acid during digestion. Additionally, boiling the seeds would potentially have a negative impact on the omega fatty acids.

Whether whole or preground, flax is significantly cheaper than chia at about $0.65 per 100 grams for pre-ground flax versus $1.20 per 100 grams for chia. However prices can vary considerably. Generally, serving sizes for a 1,100-pound horse range from about 100 grams (4 ounces) up to a pound a day depending on the reasons for feeding.

Do you have an equine nutrition question? Thunes and The Horse’s editors want to hear from you! Send your questions to


Clair Thunes, PhD, is an equine nutritionist who owns Summit Equine Nutrition, based in Gilbert, Arizona. She works as a consultant with owners/trainers and veterinarians across the United States and globally to take the guesswork out of feeding horses and provides services to select companies. As a nutritionist she works with all equids, from WEG competitors to Miniature donkeys and everything in between. Born in England, she earned her undergraduate degree at Edinburgh University, in Scotland, and her master’s and doctorate in nutrition at the University of California, Davis. Growing up, she competed in a wide array of disciplines and was an active member of the U.K. Pony Club. Today, she serves as the district commissioner for the Salt River Pony Club.

Tying Up and Hydration: How to Get a Horse to Drink

A reader’s horse who doesn’t like to drink when traveling recently tied up while running cross-country at an event. Our nutritionist offers advice to get the horse to hydrate in the future.

Tying Up and Hydration: How to Get a Horse To Drink

QUESTION. ​ Recently my horse tied-up while running cross-country. This has happened before but not for well over a year. He’s not a good drinker while traveling and barely drank 15 gallons over three days, which actually is more than normal when away from home. My vet thinks the tying-up is most likely related to hydration. What can I do to get him drinking more?

A. Having a horse that won’t drink while traveling and staying away from home is both frustrating and concerning. It can be near impossible to make a horse drink, but the good news is there are some things you can try.

My first recommendation is to increase the horse’s daily sodium intake. Sodium helps stimulate thirst, so maintaining adequate amounts in your horse’s blood is very important. Horse sweat contains a lot of chloride and sodium, so it’s possible that if your horse is sweating heavily, his sodium levels can drop, resulting in a reduced desire to drink.

ANSWER   1,100-pound horse needs about 1 ounce of salt per day for maintenance. The purpose of daily sodium intake is purely to meet maintenance needs, not to replace those electrolytes lost in sweat. Many people rely on salt blocks for their horse’s sodium, but few horses really use a salt block, at least not adequately enough to meet their maintenance sodium levels. I generally recommend giving 1 tablespoon of salt or concentrated electrolyte per 500 pounds of body weight. While a salt block should always be available, my preference is to add a source of sodium to the horse’s feed every day. This could be as simple as adding salt, or if your horse is picky, he might find a quality electrolyte more palatable.

From this base starting point, you will need to administer additional electrolytes any time the horse sweats, which includes long trailer rides to events. Feed a well-formulated and concentrated electrolyte as directed by the manufacturer. When buying an electrolyte, make sure the first ingredient is not sugar. If it is, actual electrolyte levels will not be high enough to have any meaningful effect.

Typically, I find that increasing the horse’s sodium intake does the trick for horses that don’t drink when away from home. However, there are those for whom this alone will not suffice. So other ways you can encourage drinking and get water into your horse include making sure the water is warm enough, soaking hay, putting apple juice in the water, turning grain meals into gruel, and putting a handful of grain in the water bucket. Note that if you put a handful of grain in the water, you might need to empty and clean that bucket more regularly. Anytime you put something in a water bucket, such as a handful of grain or dissolvable electrolytes, always provide a second water source with nothing added to it, so the particularly picky horse has an option to drink plain water if he refuses to drink water with additives.

Hopefully your horse’s tying-up issues are just related to hydration, and the bloodwork your veterinarian will have pulled should indicate whether hydration is the main suspect. However, you and your vet will want to rule out a couple of other causes. Take, for instance, a vitamin E deficiency. Horses with inadequate vitamin E tend not to recover from exercise as well or as quickly, and over time they generate the risk of developing conditions such as equine motor neuron disease, so having their levels checked by your vet is a very good idea.

Finally, if these things do not help, you will need to talk to your veterinarian about completing a thorough workup. It’s possible your horse could suffer from a neuromuscular condition such as polysaccharide storage myopathy (PSSM), which would cause repeat tying-up episodes. Once properly diagnosed, you can often manage such conditions successfully.

Hopefully, you can identify the cause of this issue, your horse will start drinking well, and he won’t experience any additional tying-up episodes.

About The Author


Clair Thunes, PhD, is an equine nutritionist who owns Summit Equine Nutrition, based in Gilbert, Arizona. She works as a consultant with owners/trainers and veterinarians across the United States and globally to take the guesswork out of feeding horses and provides services to select companies. As a nutritionist she works with all equids, from WEG competitors to Miniature donkeys and everything in between. Born in England, she earned her undergraduate degree at Edinburgh University, in Scotland, and her master’s and doctorate in nutrition at the University of California, Davis. Growing up, she competed in a wide array of disciplines and was an active member of the U.K. Pony Club. Today, she serves as the district commissioner for the Salt River Pony Club.

How to Create a Well-Ventilated Horse Barn

Stagnant, humid air can be the bane of your barn. Its damage might be obvious in your horse’s chronic cough or the peeling paint on your stall doors. Or it might be insidious, such as rotting wood in hard-to-see places that affects the building’s structural integrity. Fortunately, you can take simple steps to improve the ventilation of your existing barn and consider certain design elements when building a new one.

If you house your horses in a barn, keeping it well-ventilated is an essential part of their care. Download this free report to learn how you can take simple steps to improve the ventilation in an existing barn and give your horse the fresh air he needs.

Special Report: What We Know About Bisphosphonates For Horses

Navicular syndrome management changed significantly in 2014 when the U.S. Food and Drug Administration approved bisphosphonates for treatment. Sponsored by Dechra Veterinary Products.


Recently, Texas A&M researchers reviewed the current body of knowledge surrounding bisphosphonates and their use in horses. Their goal, they wrote, was to “discuss the current understanding of the strengths and weaknesses of bisphosphonates in equine veterinary medicine and highlight the future utility of these potentially highly beneficial drugs.”

Download this special report to learn what they’ve found and suggestions for pinpointing optimal use of bisphosphonates in horses going forward.

Beyond Osteoarthritis: ‘Other’ Causes of Joint Disease

Early diagnosis and proper treatment of these joint problems can make the difference in whether the horse can return to soundness.

Beyond Osteoarthritis: 'Other' Causes of Joint Disease

Early diagnosis and proper treatment of these joint problems can make the difference in whether the horse can be restored to soundness.

If you have a lame horse, you might argue with me, but I must insist: the equine musculoskeletal system is strong. This is primarily because of the large amounts of collagen found in the system’s connective tissues, such as fascia, cartilage, ligaments, tendons, and bone. Collagen is a structural protein with high tensile strength. It’s so strong, in fact, that it is comparable, weight for weight, with steel.

Alas, while strong, the horse’s musculoskeletal system is, as we are all aware, prone to injury. This is partly because the horse has been genetically selected for performance (primarily speed) from a limited number of sires. The body and large muscle groups are centrally located, perched upon long, slender bones.

An estimated 60% of lameness is caused by osteoarthritis, so that means 40% of lamenesses are caused by something else. We will look at the form and function of the equine joint, some of these “other” causes of joint disease, and how these other conditions relate to the proverbial “King of Joint Disease,” osteoarthritis (OA).

The Synovial Joint

A joint is the union of two or more bones. Of the three types of joints found in the horse’s body, the synovial (diarthroidal, or freely movable) joint is the most common type in the horse’s body. Synovial joints form where bones covered with a thin layer of articular cartilage meet. Synovial fluid, primarily produced by specialized cells in the synovial membrane lining the joint, fills the space between the bones. The entire joint is encapsulated by a fibrous capsule. Ligaments such as cruciate ligaments and menisci (discs of cartilage) can be within the joint, and ligaments surrounding the joint (such as collateral ligaments) all function together with the cartilage, bone, and synovial fluid to permit movement and transfer load between bones.

Potential Causes of Pain/Lameness

Any movable, synovial fluid-filled joint in the horse’s body can be injured. The list of joint diseases is expansive, ranging from simple, innocuous, self-limiting conditions, such as idiopathic synovitis (i.e., bog spavin), to life-threatening condylar fractures involving the fetlock joint.

No matter the joint involved, the potential causes of disease are primarily the same. However, some joints are more susceptible to certain lesions than others. For example, osteochondritis dissecans (OCD) is more likely to occur in the hock than any other joint. The most common locations (in descending order) are the distal intermediate ridge of the tibia, the lateral trochlear ridge of the talus, the medial malleolus, and the medial trochlear ridge of the talus. The stifle and fetlock can also be affected, but this happens far less frequently.

Not only can the structures located within the joint be injured, but injury can also occur to periarticular structures—those located close to, but not inside the joint, such as collateral ligaments and subchondral bone (the layer of bone lying directly below the articular cartilage).

It’s impossible to discuss all of these possible joint problems in one article. So here we will describe diseases primarily affecting the synovial membrane, to demonstrate how this single anatomic joint component can become inflamed and cause lameness via a number of mechanisms. Synovial membrane inflammation can vary from mild, nonpainful, and self-limiting to career- or life-ending, and it can negatively impact the entire joint’s overall health.

Synovitis: A Major Cause of Disease

Idiopathic synovitis

This is a chronic low-grade inflammation of the synovial membrane that is not associated with heat, pain, or radiographic changes to the joint (it’s not observable on X rays). Classic examples of idiopathic synovitis are bog spavin of the tarsocrural and tibiotarsal joints and windpuffs of the fetlock joint. Veterinarians diagnose idiopathic synovitis only when they cannot identify an underlying cause for the swelling, such as osteochondritis dissecans. The degree of lameness is variable and depends on the severity of the inflammation and amount of effusion (swelling). If the intra-articular fluid is particularly voluminous, then the synovitis can be, in certain athletic endeavors, a cosmetic issue. Experts suggest that most affected horses likely do have an underlying articular lesion that could be identified and treated if the joint was explored arthroscopically. In true cases where an underlying cause cannot be identified, idiopathic synovitis is thought to be caused by microtrauma to the articular cartilage as a result of conformation problems (e.g., being straight behind).

Acute (traumatic) synovitis

This is more serious, yet it’s another common cause of synovial membrane inflammation. Acute synovitis is often trauma-related (e.g., repeated trauma in athletic or inadequately conditioned horses) and only rarely occurs following intra-articular diagnostic analgesia or medication (joint blocks used to pinpoint lameness cause, or therapeutic joint injections). Synovitis is characterized by effusion, heat, pain, and lameness, and it occurs in joints such as the carpus (knee) and metacarpophalangeal joints (fetlock). Acute synovitis of the carpus and metacarpophalangeal joints has also been referred to as carpitis and osselets, respectively, but those are not generally viewed as the most correct or accurate terms to describe the condition.

Joint capsules of affected joints can also become inflamed. Regardless of the extent of the inflammation, treatment necessitates restoring joints to normal as quickly as possible. Rest, bandage support, hydrotherapy, non-weight-bearing physical therapy (swimming), pain management using such drugs as non-steroidal anti-inflammatory drugs (NSAIDs), and use of the free radical scavenger dimethyl sulfoxide (DMSO) are indicated.

“In most young horses the condition resolves with NSAIDs, adjustments in training, and increased fitness,” writes Dean Richardson, DVM, Dipl. ACVS, chief of surgery at the University of Pennsylvania’s New Bolton Center in his “The Metacarpophalangeal Joint” chapter of Diagnosis and Lameness in the Horse (Mike W. Ross and Sue J. Dyson, Saunders, New York, 2003).

Richardson also describes the use of intra-articular hyaluronan in mild to moderate cases and a combination of intra- articular hyaluronan and corticosteroid for a most consistently effective approach. He notes other therapies worthy of consideration, including oral glucosamine with or without chondroitin sulfate, intramuscular polysulfated glycosaminoglycans (PSGAG), or intravenous hyaluronan.

“Acute synovitis is a common condition that veterinarians treat and essentially all joint medications should be considered,” adds C. Wayne McIlwraith, BVSc, PhD, DSc, FRCVS, Dipl. ACVS, ACVSMR, Barbara Cox Anthony University Chair and University Distinguished Professor in Orthopaedics and founding director of the Orthopaedic Research Center at Colorado State University.

Some advanced or resistant synovitis cases could require joint lavage and even a synovectomy (surgical removal of part of the synovial membrane), usually performed under general anesthesia.

Chronic proliferative synovitis

This is historically referred to as villonodular synovitis. Villonodular synovitis occurs in the metacarpophalangeal joint and, like many joint diseases, appears to be trauma-related. Specifically, repeated trauma to the dorsal aspect (front) of the fetlock due to extreme extension of the joint causes inflammation and scarring of the synovial pad at this location. This dense, fibrous connective tissue can become extremely thick, and in extreme cases the clinician can easily see it when looking at the joint in profile. Secondary to continual inflammation, the articular cartilage and cortical bone (the hard outer layer of bone) underlying the mass erode.

Surgery is indicated in affected horses to remove the errant synovial pad, and intra-articular medication is generally required thereafter. This synovitis might sound relatively serious, but the outcome is typically good if the condition is caught in its early stages: return to function can be within six to eight weeks post-surgery.

Iatrogenic acute or chronic synovitis

In addition to the described joint disease etiologies, equine surgeon Barrie Grant, DVM, Dipl. ACVS, suggests considering iatrogenic (caused by a clinician) synovitis.

“Horses can react acutely to intra-articular medications (reactions to steroid crystals after injection, also known as a “joint flare”), and most everyone is familiar with that syndrome, but they should also keep in mind that there are many off-label uses of medications that go into joints (xylazine, sarapin, medical-grade silicone) that can all result in both acute and chronic synovitis,” advises Grant. “For protection, the history taking should always be proactive in obtaining any previous therapies or the possibility of previous therapy (i.e., a horse that was just claimed or purchased, or a horse that becomes lame shortly after transfer of care).”

According to Grant, for legal protection vets should demand full disclosure of all previous medical history when performing a prepurchase exam.

“It is not a game to see if you can outsmart another veterinarian,” says Grant.

Infectious Arthritis

Infected joints are characterized by rapid onset of heat, pain, swelling, and the development of a severe and/or non-weight-bearing lameness (equivalent to a fracture).

Joint infections, caused by the invasion of synovial structures by bacteria and/or their toxins, are major performance- limiting and life-threatening conditions that can occur in one of three ways:

  1. Hematogenous spread (via the bloodstream). This occurs primarily in foals, particularly preemies with high sepsis scores (sepsis being infection in the bloodstream) or multisystemic disease;
  2. Wound occurrence either directly into or close to the joint; and
  3. Iatrogenic inoculation during a joint injection or surgery.

“In adult horses, wounds are the leading cause of infectious arthritis,” says Tim Mair, BVSc, PhD, DEIM, DESTS, Dipl. ECEIM, MRCVS, of the Bell Equine Veterinary Clinic, in the U.K. “While the synovial membrane is highly specialized and able to prevent or control the proliferation and colonization of infective microorganisms, sometimes the invading bacterium can over-come these natural defenses.

“Secondary to infection of a synovial joint with bacteria, there is articular cartilage degeneration, decreased blood flow to the synovium, and formation of fibrin and adhesions within the joint,” adds Mair.

Performing bacterial cultures of the synovial fluid is a key diagnostic technique, and veterinarians can use the results to advise owners regarding both short- and long-term prognoses, reports Mair and colleagues in a study published in the Equine Veterinary Journal.

According to Mair, “As we hypothesized, horses with positive bacterial cultures from a septic joint have a poorer prognosis for survival to the time of discharge from the hospital and have a poorer long-term chance of returning to function than horses with suspected infections that had no bacterial growth in their cultures.”

It is important to note that lack of a positive culture does not necessarily mean the joint is not infected; there are multiple reasons why sampling a joint that is actually infected might garner a negative culture.

“For example, (a negative culture might result because) bacteria can be sequestered by the synovial membrane, and due to the natural bactericidal qualities of the synovial fluid,” advises Mair.

While bacterial culture outcome can be important, deciding if, how, and when to manage cases with infected joints should not hinge on these results.

“Treatment should be instituted immediately and is likely to include antimicrobial therapy—either systemic and/or locally at the site of infection—surgical lavage and drainage, and debridement of the affected joint,” says Mair.

The Vicious Circle: OA Development

“The joint is an organ,” says McIlwraith. “This means that while it is possible to define and describe diseases of particular parts of the joint in isolation, damage or disease initially affecting an isolated structure—such as the synovial membrane—can rapidly result in widespread damage and disease throughout the entire joint.”

In the case of synovitis, for example, if identified early, it likely can be managed medically via intra-articular medication and altered training. If a diagnosis and/or treatment are not prudently initiated, then the outcome will not be as successful. This is because instead of only dealing with one problem (i.e., inflammation), the entire joint and articular surface will also likely be diseased as well (OA could develop).

Unlike the inciting disease—synovitis—there is no cure for OA, and response to treatment is highly variable.

“Swift diagnosis and treatment of primary joint problems is imperative to minimize the development of OA,” he advises.

Take-Home Message

There is more to joint lameness than osteoarthritis, but owners and veterinarians might have to deal with those conditions as well as OA.

Early diagnosis and proper treatment of these joint problems can make the difference in whether a horse can be restored to soundness, or if he will end up permanently disabled.


Stacey Oke, MSc, DVM, is a practicing veterinarian and freelance medical writer and editor. She is interested in both large and small animals, as well as complementary and alternative medicine. Since 2005, she’s worked as a research consultant for nutritional supplement companies, assisted physicians and veterinarians in publishing research articles and textbooks, and written for a number of educational magazines and websites.

Does a Racehorse Know if He Wins or Loses?

And what difference would it make to the horse if he wins or loses? An equine behaviorist weighs in.

While I watching the 2015 Breeders’ Cup Classic prerace coverage, there was a lot of talk about running American Pharoah for the horse’s sake, not only so that he can win the “Grand Slam” (the Triple Crown races plus the Breeders’ Cup Classic) but so that he can retire after a win rather than after his Travers Stakes loss. “It’s for the horse” and “so he can go out a winner” seem to be implying that the horse understands winning and losing races. On the surface it seems like a nice thing to say—that the horse deserves to go out as a winner. But how does that fit with what is known about animal cognition? Does it make any sense? I think it is up for debate whether a horse even understands when he has won or lost a race. And, what difference would it make to the horse, really? It seems like it is more about what people want. Any comments or discussion appreciated.—Via e-mail 


These are really good questions on a topic that may be tough to answer without getting down into deep discussion about human-animal relationships, animal welfare, and the ethics of animal use. Certainly philosophers and animal ethicists have devoted much more intellectual thought to these questions, so I’ll just comment best I can from my perspective in equine behavior, and will try not to get too philosophical.

First of all, with my current understanding of horse cognition, my opinion would be that it is really doubtful that a racehorse understands winning or losing a race on the track. It’s not that horses cannot understand winning or losing a chase in natural circumstances, just that so much about racing is not at all natural.

In natural social contexts, horses do seem to “race” one another. Running and jumping in what looks like playful racing is a conspicuous aspect of play among juveniles, especially colts. Among adults, running occurs in a couple of contexts. Both males and females run to escape threats. Adult males also run when chasing or being chased by another male. In those natural social contexts, the behavior seems to indicate that at some level that they have “won” or “lost.” For example, one common scenario is one or more bachelor stallions challenging a harem stallion for access to females. Typically, the harem stallion attempts to chase them off. If the bachelor is run down and overtaken, the pair may interact in a ritualized posturing sequence, after which the loser of the chase retreats in a somewhat submissive posture while the winner “struts” back to his harem. But outside of the natural social context, and especially within the context of all that goes with being trained and ridden, it is not so clear that a horse could tell the difference of whether it won or lost.

I don’t think anyone really knows what the motivational state of a racehorse is at the time they are running. This is likely to become an area of increasing importance as our global society becomes more interested in the ethics and welfare of use of animals in sport. You asked, “How would you know if the horse understands?” Well, thinking about it, one place to start would be to look at behavior of race winners and losers during and immediately after a winning or losing race, carefully evaluating their subtle postures. If you detect a pattern of some subtle postures reminiscent of winning or losing in a natural social context, such that without knowing the outcome you could reliably predict from the horse’s behavior whether it had won or lost, you might be able to argue for some appreciation by the contestants of winning or losing the race. Most people can do this by watching people. A good example is tennis. If you see a clip of the players after a point is scored without any audio, you can in many instances correctly judge from their posture and expression whether the player had just won or lost the point.

Of course, with racehorses, it would be challenging to control for the potential influence of the behavior of the winning or losing jockey on the horse. Also, a well-documented psychologically mediated effect of winning or losing of males is a rise or fall in male hormone levels. If the pre- to post-race change in levels of these hormones corresponded to winning or losing status that could be additional evidence that the horse has some appreciation of winning or losing.

And what difference does it make to American Pharoah that he goes out a winner? Even if he did understand, probably not much. And I have to agree with you that it is all for the people. Your question brings to mind the risks and benefits of these anthropomorphic mistakes that seem ever more common with changing attitudes toward animals. Relating to an animal as if it is a person in many circumstances tends to go along with trying to provide better care. Handlers may be less likely to knowingly mistreat an animal that they view as more cognitively aware. On the other hand, animals are not people, and what people think as a better-quality life is often not the case.


Sue M. McDonnell, PhD, is a certified applied animal behaviorist and the founding head of the equine behavior program at the University of Pennsylvania’s School of Veterinary Medicine. She is also the author of numerous books and articles about horse behavior and management.


Noseband Tightness Study: The Two-Finger Rule Is Just About Right

Researchers found zero-finger tightness equaled 10 times the tightness of a human limb tourniquet.

Noseband Tightness Study: The Two-Finger Rule is Just About Right

Nobody knows where the “two-finger rule” for fitting bridle nosebands came from. But according to results of the latest study on noseband tightness, it makes sense.

When a rider can easily slip two fingers between a horse’s front nasal bones and the noseband, pressure levels around the horse’s face are generally acceptable. But as it gets more difficult to squeeze even one finger under the noseband at that same place, pressure on the horse increases exponentially, reaching heights that are technically inhumane, a leading equitation scientist said.

“Our pressure readings at half-finger and zero-finger tightness literally went off the screen, and we thought our system was malfunctioning,” said Orla Doherty, MVB, MSc, PhD, MRCVS, of the University of Limerick, in Ireland, and hon. president of the International Society for Equitation Scientist (ISES).

“We kept repeating the experiment, thinking, ‘We can’t possibly be subjecting live animals to that kind of pressure!’” Doherty told The Horse. “But actually, we are. Every day and at every competition.”

In their study, Doherty and her fellow researchers equipped a cadaver horse head with a standard dressage noseband as well as pressure sensors in various places along the bone and soft tissue under the noseband. Working with a cadaver head allowed them to more easily study the anatomical structures affected by the nosebands, she said. Further, it was the only humane way to carry out the study.

“Based on inquiries, we did not believe we would get ethics approval to carry out this study on live animals—to test them in a laboratory being subjected to the exact same pressures they’re getting in riding arenas on a regular basis,” said Doherty. She presented her research topic during the 15th annual ISES conference, held Aug. 19-21 in Guelph, Ontario, Canada.

Although researchers have studied noseband tightness before, this new investigation with a cadaver head gave the team more detailed insight into how pressure at individual sites along the horse’s face changes as the noseband tightens, hole by hole, she said. For example, they confirmed pressure is much higher on the bones than on the softer tissues, which can compress in response to pressure.

However, they noted that when they passed from one finger tightness toward zero finger tightness, pressure levels multiplied in an exponential fashion—possibly because the soft tissues reached their maximum level of compression, and there was no way for the horse’s facial structures to cope with the pressure.

What’s more, the shape of the horse’s nose at the area under the noseband makes it particularly susceptible to high pressures, said Doherty. The left and right nasal bones create two ridges running down toward the nostrils, spaced a few centimeters apart, with a slight dip in the center. Between the two ridges is soft tissue.

It’s the width and roundness of these bony ridges that make the difference, biomechanically, Doherty explained. Although a horse’s nose itself is fairly wide, these bony ridges are thin, having a very small radius in the circle of the rounded edge that takes the brunt of the noseband’s pressure. As the radius of curvature of any structure gets smaller, pressure levels shoot up because they’re concentrated on a smaller area—it’s just the law of physics, she said.

“These are hard tissues with very small radial measurements that just can’t offset the kind of pressure they’re getting subjected to,” she said. It’s somewhat akin to tightening and leaving a strap on a human’s hand, across the knuckles with extremely high pressures—except the knuckle bones actually have a wider radius, resulting in less pressure than what’s seen in horses’ nasal bones, she said.

“These are hard bumps that can’t move or squish or flatten out to distribute the pressure in any way,” Doherty said.

Pressures on all anatomical structures increased substantially with each hole the noseband tightened, she said. Pressures started to rise dramatically at slightly looser than one-finger tightness. But even before that, at a tightness of 1.5 fingers, pressures reached levels most humans would consider unbearable for themselves—as much as three times the pressure felt on a standard tourniquet used around human limbs to stop blood flow.

“Once you get to about 1.5 fingers and upward, we can very confidently say that the pressures escalate very rapidly on all the underlying tissues, with massive pressures exerted on the bones, specifically the left and right nasal bones and the mandibular bones,” Doherty said.

At zero-finger tightness, the pressure level was equivalent to 10 times a human limb tourniquet, she said. And this, she added, is what they were reading in a dead horse head. In a living, breathing, moving animal with nerves and blood pumping through his face, pressures are likely to be even greater—especially if the horse tries to move his mouth in any way.

“We don’t have studies on how horses feel pain in this area, but we can only assume that it must hurt, and probably quite a lot,” said Doherty.

ISES has updated its position statement to reflect these new findings and those of other studies carried out on noseband use in recent years, she said. She and her fellow researchers are planning and encouraging more research into noseband tightness. And meanwhile, riders can educate each other about the dangers of tight nosebands and continue to follow the two-finger rule—even though its origins are unknown, she said.

“The good news is that this gives us some validation for the two-finger rule, despite not knowing how that rule actually came about,” she said.

Dropping noseband use completely isn’t necessarily a good idea either, she added—especially with horses who have always been ridden with nosebands, as they could become difficult to manage and potentially dangerous for riders. “The point isn’t to get rid of them, but rather to change the way we use them and, in particular, how much we tighten them,” she said.

Take-Home Message

As knowledge on noseband tightness expands, horses might start to benefit from better training rather than reliance on gadgets to “fix” unwanted behaviors such as a gaping mouth, said Doherty. “Clamping it down is not the answer,” she said. “Instead, we need to keep our training methods really clear, using learning theory and using aids that are very precise and effectively executed so a horse understands what a bit cue is.”


Christa Lesté-Lasserre is a freelance writer based in France. A native of Dallas, Texas, Lesté-Lasserre grew up riding Quarter Horses, Appaloosas, and Shetland Ponies. She holds a master’s degree in English, specializing in creative writing, from the University of Mississippi in Oxford and earned a bachelor’s in journalism and creative writing with a minor in sciences from Baylor University in Waco, Texas. She currently keeps her two Trakehners at home near Paris. Follow Lesté-Lasserre on Twitter @christalestelas.