As the days get shorter and the leaves start to change color, your clients are (hopefully) calling you for a round of fall vaccines for their horses or health papers for upcoming shows or trail rides. These pre-winter visits are a great time to prepare them for changes to their horse’s feeding programs to compensate for the cooler temperatures. Some people may know that their horse’s nutrition needs change in the winter, but they may not know exactly what to change and what to keep consistent.
How to Talk About Nutrition
The best way to start a talk about nutrition may be to teach clients how to use the Henneke body condition scoring system. Depending on the horse’s breed, some people might think that the 1 to 9 grading scale reflects a horse’s relative fatness or thinness based on their barrel size. It’s important to show clients where fat tends to deposit or recede (crest, behind the shoulder, along the spine, tail head) so they can keep track of any changes through the winter.
A score around a 5 reflects a horse with a moderate body condition, in which you can easily feel ribs beneath the coat, but they are not visible. Most horses in full work will have a condition score of 5, although some disciplines, like endurance horses, might be slightly lower. Hunters or dressage horses might be somewhat higher.
According to Laurie Lawrence, Ph.D., professor of equine nutrition at the University of Kentucky’s College of Agriculture, research indicates that broodmare body condition should be of particular concern going into winter — even if mares aren’t currently pregnant.
“It is very clear that mares with a condition score below 5 take longer to cycle normally in the spring, take more breedings to conceive and may have lower pregnancy rates than mares that have condition scores above 5,” Lawrence said. “If a mare is already pregnant, having a condition score below 5 may result in a slightly longer gestation length and longer interval to first breedable ovulation post-foaling.”
Of course, calories are the primary factor in a horse’s body condition maintenance. Most people know that their horses burn more calories in winter as they move or shiver to keep warm. For many owners, the counter to this is to boost grain rations, but Lawrence suggests it’s best to first have them gather some information about forage.As the grass goes dormant and the horse’s diet becomes hay-driven, and calorie intake can vary wildly depending on the variety of hay and its maturity at harvest.
Alfalfa typically contains more nutrients and higher caloric loads than grass hays do. Additionally, early cut hays tend to be more nutrient-rich, since they contain more soft, leafy parts than the stemmy, more brittle late-season hay. Besides the nutrient analysis, late cut hays are also less palatable, so the horse is likely to waste more of it, especially if he’s eating from a pile out in a muddy field. Taking these aspects into account and switching to a better quality hay might reduce the need for a lot of extra concentrate.
“Many horse owners find that when they feed very good quality hay, they can reduce the amount of grain that is needed to meet calorie requirements,” Lawrence said.
A good amount of high-quality hay can have the added benefit of some heat production. As the digesta moves to the large intestine, the microbial fermentation of fiber there releases heat that is usually wasted in the summertime. In winter, that fermentation helps keep the horse warm. Grazing also allows the horse to continue the grazing behavior his digestive system is so perfectly designed to handle—which, in some cases, could reduce risk factors for colic.
Some horses score too high on the Henneke scale and could benefit from the coming cold. Keeping the summer/fall feeding program and maintaining the same exercise schedule should be all that’s needed to pull off a few pounds in time for the spring grasses.
Choosing The Best Concentrate
Depending on age and workload, horses have various mineral and caloric requirements. Most commercial feeds are designed for particular age ranges, reproductive states, or work levels, and are appropriately balanced to meet those needs when fed per feed mill instructions.
As horses move from pasture to hay, the nutrients provided to them will change, even if the hay is good quality. Pasture is higher than hay in Vitamins E and A, so a switch to a totally hay-based diet could, in the long term, cause deficiencies in those areas. Both pasture and hay tend to be low in sodium. Most horses are on concentrate as well during the winter however, and that will bring those vitamin and mineral levels up to normal.
Owners should remember that not all horses need grain. A small amount (one to two pounds) of a ration balancer can sometimes be adequate for heavier breeds that remain hearty in the cold.
For horses with metabolic syndromes, Lawrence said it might be desirable to get extra weight on them without feeding a high-starch concentrate. Soaked beet pulp is full of readily digested fiber and fat. Fat is desirable in such cases because it contains a little more than twice the amount of digestible calories as an equal amount of starch, making it very energy dense without placing the horse’s health at risk.
Another means of adding fat-based calories is top dressing corn, soybean, or rice bran oil on the horse’s food. These are highly palatable oils, and the practice works as long as temperatures in the feed room are kept high enough for the fat to stay fluid.
Keep Up With Exercise
Some mangers may be inclined to keep horses shut up in stall rest when the weather turns bad. Research as far back as the 1980s has indicated that exercise increases bone density in young horses. More recently, Michigan State University determined that excessive stall time can have a negative effect on osteocalcin concentrations, indicating osteoblast activity, and reduced radiographic bone aluminum equivalencies compared to cohorts who spent more time in pasture. Lawrence says managers need to strike a balance between shelter during poor weather and adequate exercise.
“Exercise is important for growing skeletons, so keeping youngsters in stalls when the weather is bad may not be the best for their bone development,” she said. “On the other hand, if they live outside 24/7, then a severe winter can slow their growth because calories will be used to keep warm that could otherwise be used to fuel growth. Whenever possible, young horses should be weighed regularly to make sure that growth is steady and moderate.”
Most young horses can account for slow growth in the winter with increased growth rates in spring, but that puts them at risk for bone-related disorders.
Keep In Touch With Your Clients
As with any nutrition advice, one of the most important tools you can arm clients with is an open communication pathway. Nutrition plans may need to change depending upon the severity of the season, so be sure they’re weighing or body condition scoring their horses as the winter weeks progress.