Tips For Equine Weight Gain Through Increased Body Fat

Once a horse reaches its mature size, there are two main ways that they can gain significant weight. The first is by increasing the extent of the fat stores within their body (i.e., putting on condition and thereby weight). The second is by building up their muscle. Similarly, a horse can lose weight by either losing fat or muscle.

It is important to know whether your thin horse has lost mainly external fat (that is the fat you can see and feel), muscle, or a mixture of both. Look at Equine Muscle Mass: Detecting and Monitoring Changes for more information. You can learn how to check for a loss of muscle in your older horse.

Weight Versus Condition

Often, weight is used to mean condition or the reverse. That can cause some confusion as we don’t always use condition to mean the same thing. For some, condition relates to the health of the horse’s coat (plus mane and tail). Or, it might relate to having good musculature (plus healthy skin and coat). Others may be referring to having a healthy body condition as determined by a body condition score (see A Guide To Equine Body Condition Scoring).

Here, when we mention gaining condition, we are referring to increasing the horse’s body condition score through increasing its external (and internal) fat stores. Some people refer to body condition scoring as fat scoring for this very reason.

In this article, therefore, we are discussing putting on fat rather than muscle.

Excess calories (energy) are stored as fat. While this might sound like a bad thing, all horses—like people—need a certain amount of body fat to help keep them healthy.

Being underconditioned (i.e., with reduced fat reserves) can lead to a variety of problems. These can include reduced performance in any age. In our older animals, reduced fat reserves can contribute to certain health issues, including a reduced ability to mount an effective immune response, as well as their ability to manage their body temperature.

Following are some tips to consider when you want to put on condition (and therefore gain weight). As always, these need to be adapted to the individual circumstances.

Do They Really Need to Gain Condition?

This sounds like a strange first consideration, but it is important to check that it is not just your perception that they need to put on condition. Most of us have a tendency to overestimate or underestimate the weight of our animals. It is therefore important that you have checked what their body condition score is using a recognized system (see A Guide To Equine Body Condition Scoring).

It may be that you would like to use a more objective measurement-based method such as the body condition index. However, this is really of value to identify those that may be overweight or obese (see Body Condition Scoring: Body Condition Index and Other Techniques).

Even if you are certain that they need to gain condition, it can be helpful to undertake a body condition review now so that you can monitor and check progress as you put your feeding plan in place.

Changes in condition, whether an increase or decrease, can occur so gradually that you can miss them. Recording regular milestones can be helpful.

Is There a Clinical Reason to Gain Condition?

Horses are just like us. Some seem to put on condition easily whereas others don’t even with the same feed and exercise regimen as similar horses in your herd. This might be due to individual differences in appetite, digestion, and metabolism. However, it is important to eliminate clinical or managemental reasons for a failure to maintain condition.

Certainly, a rapid change in condition can be a red flag that warrants having a discussion with your veterinarian. However, often in our older horses the loss can be more subtle but equally important. That is why you need to regularly monitor your horse’s body condition and muscle atrophy scores.

Try to identify why a horse might have lost condition. If possible, take steps to remedy the situation(s). (Check out our three-part podcast/article series on weight loss in the Further Reading below.)

Condition-Changing Scenarios

Could it be a social/behavior issue that you can address through management changes? For example, has there been a change in herd dynamics and/or are they being denied free access to feed or water? Have they lost a close companion? Some horses prefer to be fed in the company of some individuals but not others and, therefore, a loss or change in their companions can result in a reluctance to tuck into their feed or forage.

Any possible issues with the feed or forage? Has there been a recent change or are there any possible issues (e.g., mold/mites) that might have made them reluctant to eat? Has there been a lot of rain so the fields are more mud than grass? Sometimes minor changes in grass quantity or quality can be enough to ‘tip’ a horse into weight loss, especially an older horse. Don’t forget that haylage often contains more water than hay. Therefore, you might need to feed more to provide the recommended forage dry matter intake (see 10 Tips on Feeding Forage to Horses).

Could it be that as they are getting older they need more protection against either hot or cold environmental conditions? Just helping with rugs may be enough, but remember to remove and check regularly for changes in body condition.

Could known clinical issues be causing increased problems that again you could address through management changes? For example, issues with hilly, muddy fields could prevent easy movement or cause increased pain leading to a loss of condition. Have you have added a medicine into a horse’s feed that has caused the animal to be more fussy with eating?

How much are they actually eating, and are there any issues with eating? When horses are being fed mainly hay or haylage, it is really important to check how much they are eating and how much is left every day for at least 3–5 days. (See Senior Horse Loss of Appetite.) It’s important to look at how they are eating. Are there any signs of not being able to chew properly such as quidding? (See Tips on Feeding Older Horses With Dental Issues.)

Are they showing any other clinical signs that might give you an idea of what is going on so you can inform your veterinarian? Monitoring your horses when healthy under various circumstances helps you know when they are not themselves.

Can I Just Feed More?

In many cases, weight loss can simply be the result of under-supplying calories (energy) compared to requirements. In those situations, just increasing the intake of calories can be the answer. But, understanding how you can safely increase calories/energy in your individual animal’s diet becomes key.

Forage and Fiber

The first solution to consider is to start feeding as much forage as your horse/pony will eat. Be mindful of excess waste and the effect this program has on other animals in the herd.

Feeding more of the same might be a quick fix. This obviously will not work if they are already eating as much as they want or they cannot eat all of what they are being fed. In that case, hay replacers might be needed.

Even if hay replacers are not needed for some horses, you can feed some hay replacer alongside the horse’s hay/haylage. This might help if the horse’s appetite is reduced or the only forage available is of a lower energy than they require.

Alternatively, if you are already feeding as much as your horse will eat, then consider changing the type of forage to one that is more energy-rich. Typically, less mature forages provide more energy. But, the only way to assess the nutritional value of a particular forage is to have it analyzed. (Note that haylage is not automatically higher in energy than hay.)

Complementary or Bucket Feed

Firstly, check whether you are feeding the recommended amount of your current complementary or bucket feed. A simple increase to recommended levels for your horse’s exercise level might be all that is needed.

Don’t be tempted to keep increasing the size of your horse’s meals to provide more calories. Large meals are more difficult to digest and increase the risk of colic. For example, feed a maximum of 2kg (4.4 pounds) per meal (dry weight) for horses (500kg or 1,100 pounds). Always think of increasing the number of meals per day, not the size of the meals.

If your horse is prone to a clinical condition such as laminitis, colic, gastric ulcers, or tying-up, speak to a nutrition advisor before making any changes in diet.

What About Cereals?

Tolerance to cereal starch varies between individuals. This tolerance might be reduced with age in some animals. For horses prone to excitability, it may help to choose feeds containing less than 15% starch (or less than 10% for very sensitive horses).

However, recently we have realized that rather than concentrate on the percentage of the starch and sugar (NSC) in the feed, we should perhaps consider the amount being provided per meal and per day.

As a general guide to support digestive health, we recommend feeding less than 1g of NSC/kg BW/meal. For seniors in general, less than 0.5g/kgBW/meal might be more appropriate. (See Forage and Grain Tips to Reduce Equine Colic Risk.)

For animals with a history of laminitis and/or insulin dysregulation (ID), the amount of starch and sugar they can be fed in each meal can be very low. Nutrition advice is often helpful in these cases. Your veterinarian may also recommend that you evaluate your horse’s insulin response to its own feed.

Consider a Fiber-Based Feed

Choosing fiber-based feeds that are low in starch and sugar helps to support digestive health. It also might help with insulin response and reduce the risk of unwanted excitability.

What About Sugar Beet Pulp?

Un-molassed sugar beet is relatively high in the calories it can provide. It also is an excellent source of highly digestible fiber and is low in starch.

Always weigh sugar beet and other soaked feeds before soaking. The increase in volume after soaking makes it easy to overestimate how much you are actually feeding. In fact, sugar beet contains approximately 80% water once soaked. That means a scoop of ‘regular cubes’ could be many times higher in calories than a scoop of soaked sugar beet! (See 10 Sugar Beet Facts Every Horse Owner Should Know.)

Using Oils in Equine Diets

Oil is approximately 2.5 times higher in energy (energy = calories) compared to cereals and starch. That makes fortified feeds high in oil a potentially good alternative to cereal-based feeds.

An alternative is to feed supplemental vegetable oil or calcium-supplemented stabilized rice bran. It is important to remember that you should only feed fresh, non-rancid vegetable oil that has been stored in a cool, dry place. It should be introduced gradually (starting around 30-50mls/500kg horse or 1-1.6 ounces/1,100 pound horse) once daily and increasing over 7-21 days if required.

Faecal quality should be monitored and re-assessment made if there is evidence of, for example, any oil-covered faecal balls, loose droppings, or issues with palatability.

One standard cup (about 225 ml or 210 g) of vegetable oil provides about 7MJ (about 1.7MCal) of digestible energy. Depending on energy requirements, ½ to 1 cup of oil can be fed once or twice daily (up to a maximum of about 1 ml oil/1 kg bodyweight or about 0.33 ounces per 2.2 pounds of bodyweight) without specialist nutritional consideration.

The total diet should provide an additional (above the recommended intake for your horse) 1-2 IU vitamin E per 1 ml of added oil. So, depending on how much vitamin E is in the base diet, you may need to feed a vitamin E supplement. If concerned speak to your nutrition advisor

How to Tempt Your Horse to Eat

Horses are like us in that some of us become fussier with our food as we get older, but others become much less fussy. If your horse is one of the former (and dental or clinical issues have been ruled out), then consider the following:

Although potentially more appealing to the human eye, feeding mixes can make some horses more selective and cause them to pick out the bits they find most appetizing! Perhaps try them with very small meals of different types of feed, such as pellets or soaked mashes, to see what they prefer. (See A Guide to Feeding Mashes.)
Try feeding smaller meals to avoid ‘over-facing’ your horse/pony. (NB Cubes/pellets are denser than mixes, which means they can provide the same energy but in less volume of feed in the bowl.)
If using more than one feed, try feeding them in separate buckets.
Try providing very small amounts of different forages around the stable.
Adding warm water, grated apple or carrot, sugar beet, mint, fruit juice, herbs, or fenugreek (which smells of curry!) can help tempt some fussy feeders. Find what works for your horse. Remember if you are still competing to check that any additions are suitable for feeding under competition rules.

Final Words

Remember that many factors—such as changes in routine and environmental conditions—can affect appetite. This includes the presence (or absence) of certain other horses/ponies. Therefore, it is always worth checking if there is anything you can do that might address some of these situations.