Feb, 2021
Unwanted weight loss in horses is particularly topical in the winter months. But in fact, it is a problem that horses can face at any time of the year, and there are a number of possible reasons.

Weight loss will negatively impact performance, and, without intervention, a horse’s body condition score will continue to fall, eventually causing starvation. The first step to addressing unwanted weight loss is to determine the cause. Keeping an eye on the horse’s weight, body condition score and muscle build-up can help to realise the problem early on allowing you to act immediately.

Body condition scoring assesses accumulated body fat, both visually and by palpation in six areas and assigns a score to describe its body condition. Loss of body fat should not be confused with loss of muscle mass. Your horse may also look like it is losing condition if muscle mass reduces, for example, due to injury, lack of adequate exercise or if the diet does not provide sufficient levels of nutrients such as high-quality protein and vitamins to maintain and support muscles. Knowing if the horse is losing body fat and or muscle mass can help to determine the cause and most suitable method to address the issues.


Causes of weight loss

Consider the main causes of weight loss and what can be done to rectify the problem.

Simply put, weight loss occurs due to a negative energy balance. A horse will maintain condition when the calorie intake matches the horse’s energy output. If your horse is using up more energy than he is taking in, the balance will shift, and the horse will start to lose weight. To identify the cause of weight loss consider the horse’s lifestage, environment, climate, health status, and diet.



Older horses often have trouble holding condition. They may have difficulty chewing forage due to dental issues, and old age may compromise the efficiency of digestion.

An older horse with chewing difficulties may require switching to a feed which can be fed soaked such as hay cubes, beet pulp or a hard feed which could be fed soaked in order to support feed intake and digestion. If your older horse does need a ‘forage replacer’ we recommend you speak to our expert team, who will be able to recommend a suitable diet for your individual horse’s needs.

If an older horse is losing weight due to compromised digestive efficiency a more energy- and nutrient-dense diet providing increased levels of high-quality protein, calories and vitamins and minerals may help the horse regain weight.


The environment the horse lives in will also impact their body condition. Horses use calories to keep themselves warm and cool themselves down, so very harsh winters or very hot summers can exacerbate weight loss.

Herd pecking order will also influence feed intake. Horses low down the pecking order are often chased away from feed sources leading to a decreased overall intake of feed. Or soundness issues could make it more difficult for the horse to access feed in a group situation.

Another factor to consider is climate as this will influence pasture quality and intake. Hot summers and drought will result in less grass being available and decreased pasture quality. During winter pasture quality will similarly decline. It is important to always keep an eye on pasture and hay/ haylage quality, so that you can adjust the diet accordingly whenever necessary to ensure adequate calorie intake.

Underlying health issues leading to weight loss

Some horses may be underweight due to health problems which may require veterinary attention. Parasites, dental issues, infectious disease, ulcers, and chronic pain must be ruled out as the cause of unwanted weight loss before making any changes to the diet.

Some underlying medical conditions such as ulcers will require the support of a special dietary regime to help the horse gain weight and condition.

Dietary management of a horse suffering from ulcers should include ad-lib access to hay/ haylage or pasture wherever possible, providing an energy-dense and low-starch diet and feeding smaller concentrate meals. The concentrate feed should provide calories from non-cereal grain sources such as highly digestible fibres, for example, beet pulp. At Connolly’s RED MILLS our Horse Care range includes a variety of low-starch feeds relying on alternative energy sources.

Care Range Group RedMills

The most common cause of weight loss

The most common reason for weight loss is simply that the calories being fed are not meeting your horse’s daily requirements. Several options can be considered to address a lack of calories in the diet.

Forage should account for the largest proportion of your horses’ diet and can safely be fed ad lib. Consider increasing the amount of hay/ haylage you offer or allowing 24-hour access to grazing. Forage is a source of calories and is necessary to ensure normal functioning of the digestive tract. If providing increased amounts of forage is not enough to promote weight gain, calories coming from concentrate feeds must be considered.

The calorie density of the diet can be increased by feeding small, highly digestible feeds divided evenly throughout the day. Sometimes all it takes to counteract weight loss is to feed more. Increasing the amount of concentrates fed will increase total calorie intake.

Remember to feed little and often. In practice this means that the total amount of concentrates fed per day should be split up into several smaller meals. The amount of concentrates fed will determine the amount of meals offered per day. Keeping concentrates meals small will allow the horse to better digest and absorb nutrients and calories from each concentrate meal while helping to maintain digestive health.

If you are happy with the feed you are using but would just like to add more calories to the diet on a short-term basis, consider the addition of oil such as Foran Equines Kentucky Karron Oil. Choosing an oil rich in omega-3 fatty acids can also help to achieve good coat condition and benefit digestive health.

Alternatively, choose a feed specifically formulated to promote condition such as Connolly’s RED MILLS 14% Conditioning Mix. A high-calorie, barley-based muesli suitable for performance horses, which has been steam cooked to increase digestibility. If the horse requires extra calories, but it becomes too hot and excitable on a grain-based diet, choose a feed relying on ‘non-heating’ ingredients such as super fibres and oils for supply of calories. Connolly’s RED MILLS Cool’N’Condition Cubes may be ideal as they provide a conditioning, yet cereal-grain free source of calories.

Take-home message
  • Weightloss is a common problem in horses.
  • Identifying the cause is key to support weight gain.
  • Rule out underlying clinical reasons before changing the diet.
  • Determine whether the horse is receiving adequate calories in the diet.
  • Verify that the horse is indeed consuming its intended feed.
  • Adjust the diet if necessary, to ensure sufficient intake of calories and other nutrients such as high-quality protein, oils, vitamins and minerals.

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If you have any concerns on your horses weight or a question about their diet, get in touch with our expert team.

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