Preparing for Winter:

Considerations to Help Carry Your Horses Through The Cold Winter Months While Maintaining Optimal Health for The Best Post-Winter Outcome

While the last thing that most horse owners want to think about is winter, it’s clear that preparation and planning will lead to a more healthy and enjoyable winter season for both horse and rider. Cold weather complications come in numerous forms, but with the right knowhow the pitfalls of freezing temperatures can be diminished and may be avoided all together. Over time, the numbers of cold weather-related cases needing immediate veterinary care have decreased. Thanks to better information and tools available, horse owners are more aware of the risks associated with colder weather and know how to prevent them.

“I really try to coach (clients) on the importance of water quality and the presence of heated water, especially for the horses that are outside. As the water temperature drops, the horse’s water consumption goes down and that can lead to impaction colics and other health-related issues going through the winter months.”
— Douglas Langer, DVM, MS, Wisconsin Equine Clinic & Hospital in Oconomowoc, Wisconsin

The Top Winter Health Concern

Equine veterinarians Douglas Langer and Roland Thaler agree that dehydration is the biggest health risk as days grow shorter and colder. “When I’m looking at horses going into winter, one of the biggest challenges is water that’s not adequately heated,” points out Dr. Langer, DVM, MS, managing partner of Wisconsin Equine Clinic & Hospital in Oconomowoc, Wisconsin. “I really try to coach (clients) on the importance of water quality and the presence of heated water, especially for the horses that are outside. As the water temperature drops, the horse’s water consumption goes down and that can lead to impaction colics and other health-related issues going through the winter months.”

Heated water is a must-have, but what precisely is the perfect water temperature on cold days? Researchers Michaela A. Kristula and Sue M. McDonnell at the University of Pennsylvania’s School of Veterinary Medicine found that during cold weather, horses drank almost 40% more water if the temperature ranged from 45- 65 degrees Fahrenheit instead of 32-38 F. When only warm water was provided, horses in the 1994 study drank significantly more, making it the top management practice during cold snaps to prevent dehydration and gastrointestinal problems.

Originally from Pennsylvania, Dr. Roland Thaler, VMD, DACVSMR, owner of Metamora Equine PC in Davisburg, Michigan, grew up accustomed to cold winters. He recalls having the all-important family job of walking down to the creek multiple times a day with a sledgehammer to pound a hole in the ice to give the horses access to water. Fresh, not frozen, water is key; even better is warmer water with an ideal temperature of 45-65 F. If a water heater isn’t feasible or available on a particularly cold day, Dr. Thaler advises topping off buckets with hot water a few times a day, so horses drink more. Thaler advises clients to simply add 1 tablespoon of salt on top of each feeding. We’ve all heard the old adage: you can lead a horse to water, but you can’t make them drink. Well, since salt drives thirst, this simple preventive step will likely increase their water intake.

A Common Winter Misconception

Many horse owners face winter with a fear of potential weight loss that can occur with the arrival of cold temperatures. This misconception often drives greater servings of hay and feed as winter progresses. Equine veterinarians, on the other hand, may see the opposite result come spring. Dr. Langer sees more horses emerge from winter too heavy versus too light. While some extra weight may leave riders comforted that their horses are “well-conditioned for winter,” there can be deleterious impacts to a horse’s health resulting from carrying additional weight. “Excess body condition is a predisposing factor for metabolic conditions, not to mention compounding effects for horses treated for lameness issues,” says Dr. Langer.

There are certainly horses that require additional winter calories to maintain a healthy body condition, such as hard keepers — those naturally prone to be thin horses that lose weight quickly and have difficulty gaining it back — and some senior horses; but those cases are fewer and further between than those horses coming out of cold weather with an elevated and potentially-harmful body condition. “The No. 1 problem I see is horses that are overweight,” emphasizes Dr. Langer. He educates clients to run their hands over the horses’ bodies so that even with a thick hair coat, they get a good feel for that horse’s body condition. “If they start to notice that body condition increase, then I really coach them on the need to reduce their total caloric intake if need be,” he explains. This includes assessing the amount of concentrates and hay being offered and recalibrating according to any decrease in physical activity or increase in sedentary behaviors accompanying cold weather and snow or ice.

Going Hands On to Avoid the “Spring Surprise”

Discovering a horse has become too fat or too thin once their haircoat sheds out is what Dr. Thaler calls the “Spring Surprise.” For fewer surprises, Langer and Thaler advise horse owners to literally get their hands dirty. While a visual assessment is helpful, it won’t tell the whole story if the horse is carrying too much weight or not enough as winter haircoats are deceiving. When riders run hands over their horse’s ribs every few weeks, they’re better able to consistently monitor the state of the horse’s body condition. “Owners should be assessing the horse’s body condition score at least monthly, and if, for example, it’s been unusually cold, they may want to check them weekly because their weight can change fairly quickly,” Dr. Langer says. “You can’t manage something unless you measure it,” Dr. Thaler explains. He advises clients to establish a good benchmark weight on their horse going into winter, even if the measurement is done using a simple and inexpensive weight tape. In addition, keeping a written log of the horse’s body condition score and weight allows riders to make caloric adjustments based on the recorded data.

Regardless of weather conditions or the time of year, the question is: What is the ideal target body condition score? It is generally recommended to maintain adult horses between 4 and 6 on the Henneke Body Condition Scoring System that uses a 1 to 9 range based on visual appraisal and palpable fat cover of six major points of a horse most responsive to changes in body fat. A score of 1 is considered poor or emaciated with no body fat. A 9 is extremely fat or obese. Veterinarians consider a body score of 5 to be ideal. Some performance horses are commonly seen heavier than the ideal range. “I would prefer if you’re going to err on one side or the other, being just a little bit on the lean side is better than being too heavy,” Dr. Langer notes.

Common Winter-Feeding Faux Pas

There’s a common misconception that as winter sets in and temperatures drop, horses need a substantially different diet. While this adage may be true in some cases for calorie requirements, it’s important to remember that a horse still requires a balanced diet regardless of the season or temperature. Often, horses will emerge from winter with plenty of condition along their ribs but lacking in muscle over the topline or with a lackluster haircoat. This often is the result of a dietary imbalance possibly from insufficient amino acids, trace minerals, vitamins or omega 3 fatty acids. It’s commonly forgotten that even the best quality hay will lose the vast percentage of its vitamin E and omega-3 fatty acid content just six weeks after harvest.

Drs. Langer and Thaler see a common challenge in their patients: When clients reduce their horses’ winter feed to decrease calories during periods they aren’t able to ride, they often cut vital nutrients in the process. Dr. Langer says, “My general preference for horses is a ration balancer or a vitamin and mineral supplement. This helps limit the amount of grain they’re feeding with the primary food source being hay.” Adds Dr. Thaler: “If you restrict calories by 30%, you are also restricting other nutrients (trace minerals, vitamins, etc.) by 30%. So it’s crucial to ensure that you replace those in a more concentrated way.” If grains and concentrated feeds are reduced or eliminated, Dr. Thaler likes to see a horse receive high-quality vitamin and trace mineral supplements. “Don’t be afraid to restrict hay intake when you find your horse needs less calories; however, be sure to use a scale to target 1.5% of the horse’s bodyweight in dry matter daily. For example, 15 pounds of hay per day for a 1,000-pound horse,” he says. It is important that horses have hay available as much as possible, especially if grass is covered in snow. To support a healthy digestive tract, put hay in a slow feeder to emulate a high-fiber grazing type of diet and increase the amount of time that forage is available to the horse.

The combination of high-quality forage in appropriate amounts for each horse’s needs and activity level, combined with a comprehensive supplement that delivers those crucial omega-3 fatty acids, amino acids, antioxidants, vitamins and trace minerals, is an effective strategy for feeding the most ideal equine diet.

Conserving Precious Calories

For horses that tend to be hard keepers or for older horses, calorie conservation can become important during cold stretches. Dr. Langer advises that owners of hard keepers take caution prior to winter months and continuously monitor the horse’s weight. Winter stress can easily aggravate older horses who may have difficulty eating because of dental issues, etc. They can lose weight very quickly during winter and may have difficulty putting it back on in cold temperatures.

Dr. Langer pays attention to not only the quantity of winter hay but also its quality. With each client, he considers the current body condition of the horse and the quality of the hay available. He then coaches clients on if they’ll need to incorporate less mature alfalfa hay to take advantage of its higher calorie count. When horses require more body condition, Dr. Thaler prefers to use a general 30% increase in calories as a rule of thumb; starting by increasing hay, then reassessing in 30 days to evaluate the effectiveness and additional dietary changes needed. Once hay intake increases, owners may look to add highly- soluble fiber sources with controlled starch levels and oils high in omega-3 fatty acids, such as flax oil.

On the topic of calories and the gastrointestinal tract, Dr. Thaler has an interesting observation: in doing numerous gastroscopies — viewing the inside of a horse’s stomach — throughout his years in practice, he is surprised to be seeing more horses with Gasterophilus, or bots, in the stomach. Bots are the parasitic larvae of the botflies, Gasterophilus spp, that attach to the mucosal lining of the equine stomach, which can cause gastritis and may lead to ulceration in horses. “We may be judiciously utilizing fecal egg counts and deworming appropriately; however, we still need to be mindful of when we do that fall deworming,” he points out. If the deworming was prior to a hard frost, then there is the possibility that warm weather allowed for reinfestation and worms to percolate all winter.

Drs. Langer and Thaler advise active management in the use of blanketing, increased calories, monitoring herd dynamics, proactive deworming and proper dentition for those horses that may be predisposed to winter loss of body condition.

Warm On a Frosty Day

Riders tend to be keen caretakers, looking for any opportunity to make their horse more comfortable in the face of uncomfortable scenarios, such as freezing temperatures. It’s important to remember that while the weather may get chilly and even freezing, horses have their own internal heater (hello fermentation) that can easily be stoked up simply by ensuring hay is continuously available to them. “Just having some additional hay to be eating when it’s cold out really helps them get through those cold spells,” assures Dr. Langer.

While there are the fortunate horses that maintain an ideal winter haircoat as their windbreak, there are some that tend to make things more challenging. In those cases, if riders recognize their horse struggling during cold weather or wind, blanketing can help conserve precious calories by moderating body temperature. For the average horse with proper shelter from the wind, however, Dr. Langer recommends going without blankets — if possible. On the other hand, horses that are in consistent work or have difficulty maintaining a healthy body condition, he supports blankets as an important protection resource. “If we’re concerned about them losing weight, the blankets will definitely help them maintain body heat and reduce their total calorie requirements during the winter months,” he says. Dr. Thaler agrees and uses the analogy of the menagerie of coats in your closet where you can select the best coat for the type of day. Fortunately, the horse is very blessed in the “coat department.” The exception to that rule is, of course, horses that have been body or trace clipped as a result of Cushing’s disease for example, removing their natural winter coat and protection mechanism. “Even with a normal, healthy horse of adequate condition, you have a decision to make. The horse can either burn additional calories from their food source or you can conserve calories by making it easier for them to stay warm in a winter blanket during any stretch of inclement weather,” advises Dr. Thaler.

While some horses have a full winter coat and turnout to bask in whatever sunshine is available, others may require blanketing and indoor housing. It’s important to note that bacteria thrive in warm, dark and moist environments; for instance, a dirty coat under a dark, warm, possibly moist blanket can become a breeding ground for unsavory characters. Riders can consider using a rubber curry grooming brush to frequently remove the buildup of dander and dirt, helping to prevent the unwanted bacteria. On appropriate sunny, warmer winter days, Dr. Thaler encourages owners to pull blankets and give horses access to sunshine as well. Not only is it a good dose of vitamin D, but the ultraviolet light serves as a natural sanitizer, reducing overgrowth of bacteria or dermatophilosis of haircoat.

Expect the Best, Prepare for the Worst

It’s a good credo to live by — anticipate the worst situations and prepare for them accordingly. The winter months include plunging temperatures, snow, ice as well as possibility of power and water outages that can often accompany the season. Dr. Thaler reminds clients to prepare for the potential pitfalls. “The time to prepare is now, not when the blizzard is hitting,” he says. An adequate water supply is critical, as is ensuring emergency generators are properly functioning. In addition, have enough hay reserves to last through any period when bad weather may interrupt hay sourcing or delivery.

Indoor Air Quality

While not the case for all, some horses may spend more time inside during the winter months, which raises the potential for respiratory problems, veterinarians caution. To avoid the potential issues associated with an indoor environment, riders should consider where hay is stored, when they choose to sweep and even whether to wet hay prior to feeding to minimize dust in the air. “Barn environments or horses breathing the dust all day increases the incidence and severity of lower airway inflammatory disease,” cautions Dr. Thaler. In addition, Dr. Langer advises clients to monitor the hay fed, making sure that it’s free of dust and mold. These commonly create respiratory issues later in a horse’s life. In barns that are closed, it’s easy for air quality to quickly diminish.

Exercise is Medicine

Jack Frost’s arrival doesn’t mean that riding should stop. If horses are properly cooled post-ride and blanketed according to haircoat, they do well even in winter. With appropriate management, extreme caution only becomes a factor when the temperature drops below 20 F. Dr. Thaler advises clients to exercise horses but at a lower intensity in freezing temperatures. “The horse’s nose is very good at warming air, as long as you allow it time to do so. Intense cold can cause trauma to the lungs, so reducing intensity of work during those times is a good idea,” he says. Post-ride, horses should be properly cooled down, and blanketing should be adjusted according to the temperature. It should also be noted that while we generally think to provide electrolytes in summer, if your horse is sweating during winter rides, electrolytes should be considered to replenish what is lost in sweat and to encourage hydration.

Involving Your Veterinarian

“I think it’s important that horse owners see their veterinarian at least twice a year,” advises Dr. Langer. Veterinarians can alert owners to potential concerns you can keep an eye out for over the winter. While poor dentition can impact a horse’s ability to properly maintain weight, it provides an example of the need for proactive care. “Sometimes as a horse owner, we don’t see some of the small changes that are occurring in our animal, but your veterinarian will often pick up on things earlier than you may just because they don’t see them every day,” Dr. Langer explains. From consulting on the ideal diet and any necessary dietary changes needed in preparation for or throughout the winter months, to ensuring that a horse’s body condition is kept ideal and their metabolic health is on track, a veterinarian will offer an invaluable perspective.

Contributing Veterinarians