Horse Body Condition Score

Horse Body Condition Score

How to tell if a horse is too fat, too thin or just right.

Overweight horse

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How do you know if your horse is too skinny? Or overweight? 

Horses are like people in that they come in all shapes and sizes. But being too thin or too heavy can affect their health, fertility and performance. It is the duty of the owner to ensure the horse falls into the “just right” category.

What is a body condition score?

A body condition score, or BCS, is a tool that describes the relative fatness of horses. Horses can have a body condition score of 1 to 9:

  • 1 = emaciated
  • 9 = obese

An ideal BCS would be a 5, however, a slightly higher or lower score might be acceptable depending on the horse’s use.

How is a body condition score determined?

The score is determined by examining the condition of the neck, withers, loin, tail head, ribs and shoulder. The stomach is not a good indicator of body condition. Horses can have a big belly and still be in poor condition due to consuming low-quality forage, having internal parasites or simply being out of shape.

“If we expect our horse to perform to the best of his ability, we have to give him every chance we can in terms of his physical condition,” says Teresa Slough, an equine nutrition specialist at Kansas State Research and Extension.

How do you know if your horse is too skinny?

Body Condition Score 1: A horse with a BCS of 1 will be emaciated, meaning his entire skeleton is visible and there is virtually no fat on the horse.

“Horses in this range will definitely experience a decrease in fertility and performance and, in a worst-case scenario, death,” Teresa says.

Body Condition Score 2: Although, a BCS of 2 is better than 1, it still isn’t healthy. There will be a slight fat covering over the backbone and ribs, but for the most part, all bones will be visible.

Body Condition Score 3: A horse with a BCS of 3 will still be thin, but is far better off than a 1 or 2. These horses will have fat cover over their ribs, but the ribs are still noticeably prominent. Individual vertebrae can’t be distinguished, but the horse will look thin through the neck, withers, tail head, loin and shoulders.

How do you fatten a horse? 

The first step to helping horses with a low BCS is to contact a nutritionist, veterinarian or both immediately.

“Horses with a low BCS are not getting enough energy in their diet,” Teresa says. “This could be due to old age, poor-quality feed, not enough feed, bad teeth, internal parasites, disease, sickness or a combination of problems.”

Horses can only eat 2.5 percent of their body weight in dry matter per day. Therefore, when feeding an emaciated or thin horse, feed a concentrate in addition to high-quality hay, like alfalfa.

Teresa also recommends adding a fat source to their diet. Fat contains 2.25 times more energy than carbohydrates and will help pack on the pounds. There are many different fat sources, but the most common in the horse industry are vegetable oil and rice bran.

Jason Shelton, the nutrition excellence director at Cargill Animal Health (parent company of AQHA Corporate Partner Nutrena), suggests feeding probiotics, a dietary supplement containing potentially beneficial bacteria or yeast, to increase the digestion of feed. He also says feeding horses separately two to three times per day will ensure that thin horses are getting the nutrients they need.

“It generally takes about one month to change one point on the BCS scale,” Teresa says. “Make changes to the diet gradually to avoid microbial upset in the digestive tract.”

How do you know if your horse is at the right body condition? 

Body Condition Score 4: A horse with a BCS of 4 is moderately thin, but considered healthy. Being moderately thin is beneficial in some high-performance events, such as racing and endurance. Horses will not look obviously thin; however, the ribs are still slightly visible.

“These horses are certainly not fat, but they aren’t unhealthy either,” Teresa says.

Body Condition Score 5: A BCS of 5 is considered ideal for most horses. These horses’ ribs can be easily felt, but not seen. The neck, withers, tail head, loin and shoulder do not look thin and blend smoothly into the body.

Teresa recommends assessing the horse’s activity level and then deciding how to maintain a BCS of 5, if change is necessary.

“Most horses can maintain a moderate BCS with average-quality hay,” she says. “Performance horses probably need a concentrate and a high-quality hay to meet their energy needs and maintain optimal condition.”

Body Condition Score 6: A BCS of 6 is considered moderately fleshy. This horse will begin to have fat deposits throughout the body, particularly over the ribs, and will have a small groove down the back.

This score is recommended for broodmares due to the intense energy requirements of late gestation and lactation. Mares can be fed at maintenance for the majority of their pregnancy, but Teresa says their energy needs will increase by 20 percent during the last three months of pregnancy. When the mare begins lactating, her energy requirement will increase by 80 percent. If a mare has a BCS of 6, she can lose a little bit of weight due to lactation and still have a healthy BCS.

Teresa says some show horses also tend to have a BCS of 6, although it is due to visual preference and not need.

Body Condition Score 7: A horse with a score of 7 is fleshy and has spongy-feeling fat all over his body. The ribs can still be felt, but fat is noticeable between each rib. The horse will have a distinguishable crease down the back and a crested neck.

This score may also be acceptable for broodmares, particularly those that tend to have big foals or lose a lot of weight during lactation.

If the horse is considered at maintenance, meaning it does not have extensive energy requirements, Teresa suggests eliminating grain from the diet, limiting fat intake and feeding lower-protein forage.

“People feed grain because that’s what everyone does,” Teresa says. “We have really put horses into an artificial environment by feeding them energy-dense feeds and limiting their exercise.”

Most horses can live on low-protein roughage, such as prairie or brome hay, without any type of grain or fat supplement.

“If a horse is overweight, people tend to see a ‘hay belly’ and cut back on its forage intake,” she says. “This can cause a huge upset in the horse’s digestive tract if its hay consumption is reduced and the concentrate is left the same.”

How do you know if your horse is overweight?

Body Condition Score 8: A horse with a BCS of 8 is no longer considered healthy. This horse has a noticeably thick neck, the area on either side of his withers is filled with fat, the tail head fat is very soft, and there is no distinct separation of shoulder and girth.

Body Condition Score 9: By the time a horse reaches a BCS of 9, there are fat bulges on his neck, withers and shoulder. There is no distinguishable flank area, and patchy fat appears over the ribs.

Health Concerns for Obese Horses

Obese horses are susceptible to:

  • Insulin resistance
  • Joint issues
  • Equine metabolic syndrome
  • Chronic laminitis
  • Colic
  • Founder
  • Inefficient at regulating body temperature

Feeding an Obese Horse

An obese horse should be fed a low-protein roughage and no concentrate.

“If his needs are met with a fairly low quantity of feed, he gets done eating quickly and has boredom vices, then you can put some sort of very low-quality forage in front of him,” Teresa says. "Then he can munch on something that will keep him entertained without contributing to his obesity."

She says low-quality forage is very indigestible and should only be fed to prevent boredom and not to meet the horse’s energy needs.

Is it better for a horse to be over- or underweight?

“People think fat is better than thin, when in reality, neither are healthy for the horse,” Teresa says. “A skinny horse looks bad to everybody, but most people don’t realize the hazards that come from the other end of the spectrum.”

She says the best way to prevent straying from an appropriate BCS is to monitor horses closely. If the horse becomes too thin or too heavy, address the problem immediately.

Preparing for Winter

  • Horses drink an average of 10-12 gallons of water per day. Fresh water should be available at all times. In the winter, if heated tanks are unavailable, ice should be broken several times a day. (Here are some tips for managing frozen horse water.) If a horse goes off feed, check his water. Horses will not eat if they are thirsty.
  • A horse’s energy requirements increase by 1 percent for every degree below 16 degrees F. Digesting forage creates more heat than digesting grain, so ample hay should be provided when conditions are harsh.
  • If horses are on pasture, provide hay if the grass is low-quality or snow-covered.
  • If a horse tends to lose weight in the winter, increasing its BCS by one point could be beneficial. Monitor your horse in the fall and spring to establish your plan of action to maintain his winter BCS.
  • Always float teeth and deworm several weeks before winter.
  • Exercise tends to be limited in the winter. Watch easy-keepers to make sure they don’t reach an unhealthy score.

Make the Safe Choice for Your Horse's Nutrition

SafeChoice Horse Feeds, from AQHA Corporate Partner Nutrena, are where good equine health starts. Each product in the SafeChoice line has controlled starch levels that may help support horses who have metabolic concerns, while added-fat options improve energy and enhance performance. Learn more about SafeChoice products.