Stormy Weather and Horses

Brace yourselves, folks. Old Man Winter's on his way again, and that means horsekeeping is about to get a good deal less pleasant. Between the snow, the ice, the mud, and the howling winds, you and your horse are going to have a lot to contend with.


Winter pasture

Many farmers place round bales of hay outside in paddocks for their horses' use in winter, but there are some risks involved.

The good news is that horses are naturally well-equipped to weather practically everything that winter can dish out. They are far more tolerant of cold conditions than we poor hairless humans are; in fact, horses tend to be far more stressed by heat than by cold. Left to their own devices, almost all equines, even those originally from desert climes, will successfully acclimate to chilly weather, growing winter coats that are astonishingly efficient at helping them retain heat and shut out the damp. The density of this hair coat, and the direction in which the hair grows, provide a weather shield so complete that horses can stand in the middle of a storm until ice forms on their backs, without the skin ever becoming chilled.

The equine winter coat has a "pile" that traps an insulating layer of air next to the skin; it is also naturally greasy, which helps it repel snow, ice, and sleet. A full mane and forelock will act as a waterproof screen for the head and neck, and the equine tail helps protect the delicate skin of the peri-anal region and the inner thighs when the horse adopts his characteristic rump-to-the-storm stance.

As cleverly designed as his winter coat is, though, it won't protect your horse in all conditions. In the absence of winds and precipitation, he can withstand temperatures down to -40� Fahrenheit (which is also about -40� Celsius) without difficulty. But when bone-chilling winds whistle in, they can ruffle the hair and disturb the insulating layer of warm air trapped among the individual hair shafts. Wet weather, especially cold, driving rain or sleet, can flatten the hair coat to the skin, and subsequent moisture evaporation from the surface of the hair only serves to chill things further. (Snow, surprisingly, is not that chilling--in fact, in some circumstances, it can become an insulator.)

The combination of a cold wind and rain or sleet is probably the worst case scenario for a horse. Under those conditions, without shelter, he can quickly become chilled. Older horses, in particular (from their late teens on up), tend to have difficulty maintaining their internal temperatures in such circumstances, and are at risk of losing significant amounts of weight in the winter months, a loss of condition that sometimes can be very difficult to regain in the spring.

It's also possible your horse might have his natural protection clipped away, leaving him practically defenseless against wind and weather. If you plan to keep your horse in steady work throughout the colder months, a heavy winter coat can be a liability, trapping sweat close to the skin and making your horse susceptible to post-exercise chilling. Not only that, but the wet hair seems to take forever to dry, even when you cover him with coolers and walk him...and walk him...and walk him. Body-clipping him to remove all or part of his winter hair will leave your horse better prepared for exercise, but naked and shivering otherwise. So, it's essential to provide him with protection in the form of weatherproof blankets and shelter from the elements when he's outside.

Whether you prevent your horse from getting very furry by beginning to blanket him as soon as the days start getting shorter in the fall (the growth of winter hair is triggered by dwindling hours of daylight, not by the temperature), or whether you body-clip him, you've short-circuited the natural process of hair growth. Shelter from wind and wetness, and warm "blankies" are part of your responsibility if you go this route. So is a diet that will provide your horse with the fuel to keep his internal temperature at a comfortable level.

Feeding For Heat

Given the chance, horses will lay down an insulating layer of fat under the skin in the fall, as part of their winter survival strategy. Therefore, altering your feeding program for the upcoming winter by providing some extra calories will go a long way toward helping your horse brace himself for the bitter winds. Although you might want him in fighting trim during the summer months, it's okay to let him put on a few pounds come autumn, particularly if his performance schedule is winding down for the year. (Truth be told, even horses which are active well into the Christmas season, such as foxhunters, can benefit from a little extra rib-covering in chilly weather.)

Horses have to work harder to maintain their internal body temperature when the thermometer plunges. In order to keep them from losing weight once the temperatures reach the freezing mark, you'll need to provide about 15-20% more feed per day for every 10� Fahrenheit drop in the temperature below 30� F.

Interestingly, it's hay, not grain, that is the best choice for helping your horse generate body heat. High-fiber feeds are digested in the cecum (part of the large intestine) by bacterial fermentation--and since cellulose and other fiber components are tough to break down, it's a process that generates lots of warmth. By contrast, grain, which is digested in the small intestine, is easier for the horse's system to break down, so it creates less heat.

Providing more hay is a fairly simple process for most operations; just feed an extra flake or two per meal, and monitor how much your horse eats and how well he maintains his weight. This is one instance when you might want to seek out hay with a slightly higher legume content than grass, even for your mature horses. Although your horse's protein requirements don't increase in the winter months, higher-protein legume hays are also higher in energy and nutrients, and that bit of extra energy might be a boon when temperatures plunge.

When you consider increasing the amount of forage your horse eats in the winter, remember that his pasture will likely no longer be providing any useful contribution to his diet. If it's not covered in snow, the grass there will be dead or dormant, with practically no nutritional value. In order to keep your horse from snacking on your fence posts (or each other) throughout the winter months, you'll want to offer some hay as a grazing substitute when he's outside. But between the wind and weather and your horse's wasteful habits, you'll need to allow at least 25% extra for wastage. When the ground is snowy, some horses would rather trample and sleep in their hay than eat it; it might be the only dry spot around!

Many farms place round bales of hay outside in paddocks for their horses' use throughout the winter. While round bales are a relatively cheap and low-maintenance fiber source, they do come with some risks. When left out on damp ground in damp weather (particularly if the temperature keeps fluctuating above and below the freezing mark), round bales are prone to going moldy. Sarah Ralston, VMD, PhD, Dipl. ACVN, an equine nutritionist with the Department of Animal Science at Rutgers University in New Jersey, says, "Unless (round bales) are set under cover and off the ground, the risk of botulism or mold-induced disease is far too great, in my opinion." (Botulism can gain a foothold if the moisture content and pH of the baled hay are too high, or if, as sometimes happens, a small animal or bird is unfortunate enough to get caught in the baler and perishes, smothered in the bale. The bacterium can multiply in the carcass.) Specially designed feeders for round bales can help reduce risk of molding, and are best used under the cover of a run-in shed. The alternative is to provide piles of hay from small rectangular bales on a daily basis. (To avoid squabbles among your herd, space the piles out of kicking distance, and provide at least one more pile than the number of horses.)

Feeding hay indoors minimizes wastage, but that, too, comes with certain risks. When the weather turns foul, your horse might spend an increased amount of time indoors, confined to a stall--and if he's eating hay that's dusty or moldy, he could be at increased risk of respiratory problems. (Inadequate ventilation is a common problem in barns, chiefly because we tend to build them more with our own comfort in mind rather than our horse's. In an effort to shut out every draft and keep things snug and warm, we make it impossible for molds and dust to escape the environment. As a result, the air inside a winter barn quickly can become noxious.)

To decrease the risk, feed only the highest-quality hay you can find, and discard any that shows signs of moldiness (generally noticeable as white matted or fuzzy patches within a flake), smells musty, or raises clouds of particles when dropped to the floor from a height of a few feet. Feed your hay on the floor of the stall, rather than in a haynet or rack, which would force your horse to tilt his head up to access the feed (allowing mold spores and dust particles instant access to his nasal passages). If temperatures permit, consider soaking your hay for about 15 minutes prior to feeding, to reduce the quantity of airborne particles. Finally, resist the temptation to lock the barn up tight; it's best to allow some air circulation, even if you have to sacrifice a little human comfort.

Comfort Food

Although extra calories are best provided in the form of fiber feeds, if you have a hard keeper in your barn, you might want to consider additional ways to boost the energy value of his ration to help him maintain a healthy weight throughout the winter. If your horse just won't eat any more hay than he's eating now, gradually begin to increase the amount of grain he receives, working up to about 10% more. Or you can provide calories without significant extra bulk by increasing the amount of fat in his diet; vegetable oil and rice bran are two easy ways to accomplish this. (There also are a number of added-fat commercial grain mixes on the market, which are ideal for those with finicky appetites.)

Ralston notes that extra calories are particularly important for older horses in winter. She recommends that horses on the high side of 20 years be fed at least 120% of the National Research Council's recommendations for daily intake (which is from 1.5% to 3.0% of the horse's body weight). "Some horses need even more than this," she says. "I've found some can go up to about 133% of NRC." Remember, too, that many older horses have poor dental health. If your geriatric can't manage to eat hay comfortably, you will have to substitute an easier-to-chew fiber source, such as chopped hay, soaked hay cubes, beet pulp, or a "complete feed" pellet that has a high fiber content. There are several softer-texture, high-fiber feeds designed specifically for older horses that you might also want to consider.

What about the "traditional" winter meal, the hot bran mash? While bran is a fair fiber source, nutritionally, it's not that great a choice for everyday feeding. It's excessively high in protein (averaging 16-17%), low in most vitamins (except the B vitamins thiamin, niacin, and riboflavin), and most importantly, has a high phosphorus content which, over time, can interfere with the horse's balance of calcium and phosphorus in bones and muscles. However, a bran mash probably does no harm if it's fed no more than once a week (and because of its calcium/phosphorus imbalance, never to young, growing horses). If fed on the "sloppy" side, it can even help increase your horse's water intake. But its warm, comfort-food feeling doesn't really significantly contribute to warming your horse's insides--not nearly as well as offering such a meal contributes to warming your own!

Better than bran as an alternate fiber source is soaked sugar beet pulp, which can also be served warm, if you like, on chilly nights. Beet pulp contains about twice as much fiber as bran, is highly digestible, and is high in calcium rather than phosphorus. This makes it a more suitable choice for most types of horses, though admittedly it doesn't have bran's extremely high taste appeal! If you decide to feed beet pulp in winter, either mix up just enough for one meal's worth at a time, or find a heated environment in which to store the soaked ration between feedings; left in an unheated barn, it will likely freeze.

The Most Important Nutrient...

Your horse's water intake is a crucial consideration for winter feeding. Water tends to be a "forgotten" nutrient at the best of times, and yet without it, nothing in your horse's body will function. Water intake is a special concern in winter because it's common for water troughs and water buckets to freeze, leaving your horse with nowhere to get the gallons of water he needs every day. On top of that, your horse's feed has a lower moisture content in winter (grass, for example, is more than 70% water, while hay is less than 10%). The incidence of impaction (constipation) colic tends to rise significantly in the coldest months, and many researchers feel that the reason is inadequate water intake.

By the way, snow is not enough to take care of a horse's prodigious need for water, even when it's available in abundance. If you depend on snow to take care of your horse's water needs, your horse will be chronically dehydrated and at risk for impaction.

In order to encourage your horse to drink, make sure that he always has access to clean, liquid water. Encourage further water intake by soaking his feed in warm water. Try to keep on top of the ice formation in buckets and troughs, breaking the surface for your horse several times a day. You can buy submersible bucket heaters, but the equine tendency to play with electrical cords makes them potentially risky. A better option is the newer buckets with heating elements sealed right into the sides.

As for your outside water trough, place it in the sunniest spot available, and bank dirt around its sides to help insulate it. You might want to try covering part of the top with plywood, leaving a small area free for drinking. Submersible heaters usually can be rigged up safely in a trough situation (with the electrical cord reaching back through the fence line), and while they use a lot of electricity, they are infinitely valuable in terms of time saved chopping through the ice every day. Or you can use the low-tech method: float a large rubber ball in the trough, so that when ice forms, you or your horse can push down on the ball and free up a spot to drink, or at least a starting place to break the ice.

Whenever possible, offer your horse warm water (at a temperature of about 45-65� F. Studies have repeatedly demonstrated that a horse's water intake in winter increases dramatically if he has access to warm water--and if it helps prevent a life-threatening colic, it's well worth the extra effort. A bucket of warm water, offered several times a day, can be a particularly valuable consideration for older horses, who because of their decreased digestive efficiency might be at special risk for impaction colic.

A Parting Thought

Winter is without a doubt a high-maintenance time of year, and in the midst of all the hassle, it can be surprisingly easy to forget to monitor your horse's condition. Blankets and thick winter hair coats sometimes can hide a horse which is losing condition and getting ribby. So, pull that blanket off on a regular basis to see the horse underneath. Even if your horse is living outside, and you're not using him during this season, don't neglect to check on him, and make sure he's maintaining good weight. A horse which is too thin will be unable to maintain his internal body temperature effectively, and will most definitely not be enjoying the winter chill.

About the Author

Karen Briggs

Karen Briggs is the author of six books, including the recently updated Understanding Equine Nutrition as well as Understanding The Pony, both published by Eclipse Press. She's written a few thousand articles on subjects ranging from guttural pouch infections to how to compost your manure. She is also a Canadian certified riding coach, an equine nutritionist, and works in media relations for the harness racing industry. She lives with her band of off-the-track Thoroughbreds on a farm near Guelph, Ontario, and dabbles in eventing.

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