Winter Feed: Water Intake Is Key

Drinkable water is the most important element of good winter care. Note we said “drinkable.” The complications of insufficient water intake — dehydration, shock, colic — can occur within just a day or two. Impaction colic is the most common symptom, although it may get blamed on the dry winter diet, less exercise and even parasite problems, but usually the reason is inadequate drinking.

Granted, a horse will drink less water in the winter than the summer because he sweats less — just as we do — but he still needs to consume a minimum of 3 to 4 times as much water as hay to keep his body functioning properly. If he’s on hay and grain, he needs 3 times as much water as solid food. A good rule of thumb to remember is that a horse eating 20 to 25 lbs. of hay a day needs to drink at least 8 gallons of water.

The basics ways to increase water consumption are:

• Add 2 tablespoons/day of table salt to your horse’s feed (salt triggers the drinking instinct).

• Incorporate wet feeds/mashes as a source of supplemental water (it’s not enough, but it helps).

• Like you, your horse prefers warmer water in colder weather. You can serve warmed water twice a day, the same time as feedings, but you must do it consistently).

If the barn doesn’t have a nearby hot-water supply, consider a bucket heater such as Farm Innovators’ Bucket Heater (, 800-277-8401). This large coil will warm 5 gallons of water to 100?° in about 20 minutes. It’s thermostatically controlled and can be left in the bucket for constant heating, but we don’t recommend this, as it’s too tempting a toy for a bored horse. Cost is about $30.

For stalls and run-in sheds, consider investing in heated water buckets or tank deicers such as the product line of Allies Precision Industries (, 800-627-6179). These products have built-in thermostats to turn the heater/deicer on and off as necessary, and the heater and thermostat are built into the bucket itself, nothing floating around for the horse to play with. A standard stall-size bucket runs $30-$35.

Extra Calories
Once the temperatures drop below freezing, your horse needs more feed to maintain body heat. Most horses need an increase of 10 to 20% feed in the winter over maintenance feed intake in warmer temperatures. Horses with a good winter coat or blanketed horses can often meet their needs without losing weight if fed free-choice hay, but many horses also need an added calorie source.

Regularly check your horse’s condition to be sure he’s maintaining his weight. Thick winter coats make horses look heavier than they are and may even lead to deceptive weight-tape readings. Hands-on evaluations are more accurate. Check weekly to see how easily you can locate the horse’s ribs, shoulders and hip bones under his coat, and how much fat is around the tail base.

The bulk of your horse’s calories should come from fermentable fiber, predominantly hay. This is always true, of course, but remember that the fermentation of fiber produces body heat. A good starting point for a winter diet is 2% of the horse’s body weight/day as hay. This means 20 lbs. for a 1,000-lb. horse when the temperature is at or above freezing and 2.5% (25 lbs. for a 1,000-lb. horse) when at or below freezing. Some horses will consume as much as 3% of their body weight in hay, others won’t.

If your horse was already on a hay-and-grain diet before winter, you can keep the same feeds, but it’s wise to adjust down the grain and up the hay.

If you’re starting with hay only or predominantly hay and need a more concentrated source of calories, consider meals that are high in readily fermentable fiber sources, like beet pulp, to get both a more calorie-dense meal and the benefit of internal heat from fermentation. Mashes are a good choice, especially since they contain water.

High-fiber mashes are best since they are filling, take longer to exit the stomach, and keep the horse warm from the heat of fermentation in the colon. Some appropriate substitution guidelines are:

• Complete feeds. Pelleted complete feeds vary in their calorie content. If the feed recommendation is for 1% of the horse’s body weight/day, the calorie content is likely about double that of hay, and you should begin substituting at a rate of 1 lb. complete feed for 2 lbs. of hay. If 2% of body weight is recommended, substitute on a pound per pound basis. Complete feeds will soak up about twice their weight in water.

Example: Horse’s original diet consisted of 20 lbs. of hay and 8 gallons of free water. Substitute 2.5 lbs. of a complete feed designed to be fed at 1% of body weight, which means you can take away 5 lbs. of hay. The total volume of feed is reduced to 17.5 lbs., so minimum water requirement drops to around 7 gallons. The 2.5 lbs. of complete feed will soak up about 5 lbs. (5/8 gallon) of water, leaving a remaining water requirement of just under 6.5 gallons, for a reduction in free-water requirement around 20%

• Hay cubes and pellets. These take longer to soak into a mash, but it can be done, and the hay will absorb water to about the same extent as a complete feed. The conversion rate in terms of calories varies widely from horse to horse and is heavily dependent on how well the horse is chewing his long-stem hay. Good chewers may only see a 20% or so improvement (i.e. need about 20% less pelleted or cubed hay than loose), while a horse that doesn’t chew well may get as much as a 50% increase in calorie yield from cubed or pelleted hays than regular hay.

Poor chewers will benefit from minimizing their long stem hay and providing the bulk of their hay as a cube or pellet mash. Otherwise, use hay cubes and pellets primarily for flavor and variety in mash recipes.

• Beet Pulp. Beet pulp is the premier mash ingredient for winter feeding. It holds up to four times its weight in water and provides twice the calories as average hays.

Example: A horse getting 20 lbs. of hay/day originally can get the same calorie yield from 4 lbs. of beet pulp and 12 lbs. of hay. Water requirements then drop 20%, to a total of about 6.5 gallons. The 4 lbs. of beet pulp will soak up 16 lbs. of water, a total of 2 gallons, leaving a remaining water requirement of only 4.5 gallons, a reduction of almost 50% over the free-water requirement of an all-hay diet.

• Bran. Wheat bran is the traditional favorite for winter mashes. It smells wonderful, most horses love it, and it’s calorie dense compared to hays. But, unless the horse is receiving wheat bran on a regular basis, the colon may not ferment it efficiently and some of the calorie benefit is lost.

Sporadic feeding of large bran mashes may even have a laxative effect because of poor fermentation, leading to some loss of water in the manure, which is definitely not the effect we’re after.

Using bran as a mash component rather than the sole ingredient and feeding it regularly helps avoid the laxative, water-losing effect without sacrificing the taste appeal. Combining bran with other ingredients can also result in natural mineral balancing without the need to add sup plemental minerals.

• Supplements. Your horse needs the same basic minerals and vitamins in winter as he does at other times of the year, but shortages may have even greater consequences in terms of poor resistance to infection, skin and hoof, health, and the ability to heal wounds and recover from injuries.

Continue vitamin E supplementation, at least 2000 IU/day, for good immunity. Provide 4 oz./day of a 50:50 blend of rice bran and stabilized flaxseed for horses on predominantly hay diets, or 1/3 rice bran and 2/3 flax if getting hay and grain. This will provide the essential fatty acids. Horse Tech’s Nutra-Flax ( 800-831-3309) is a good, no frills source of ground stabilized flax.

Seeds like sunflower can be substituted for the rice bran, or feed pumpkin seeds for a good balance of omega-6:omega-3 fatty acids. Grass also contains a variety of naturally occurring plant antioxidants lacking in dried diets, but treats of fresh carrots, apples and berries will provide these.

Bottom Line
Overall, most horses tolerate winter weather well. However, they do need added hay to produce adequate body heat during the winter. You also need to ensure adequate water consumption, based on hay consumption and work levels, of course. Mashes are excellent ways to add water and fiber, and we prefer beet pulp as the main ingredient in these mixes over wheat bran.

Also With This Article
”Put It To Use”
”Gourmet Mash Recipes”

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