Feeding the Poor Doer

Feeding the poor doer can be a challenge and there are a multitude of reasons why a horse might be underweight or struggle with their condition – for this reason, the solution is not always just as simple as feeding them more. The horse’s forage and grazing are arguably even more important to think about than what’s going into the bucket, and any underlying health problems also need to be taken into account.

What causes weight loss in horses?

Weight loss can be caused by a number of factors, some of which can be managed with feed or are feed-related health conditions. This is why there is not a clear, “best” conditioning feed, as certain feed types are more suited to some horses than others, and health problems, such as laminitis or colic, also need to be considered. Poor dentition, such as sharp edges or loose teeth, could result in the horse struggling to chew the feed properly and thus being unable to digest it fully, as well as affecting appetite. A worm burden due to poor worming management can also cause weight loss regardless of what is being fed.

Stressful environments where the horse is constantly being disturbed or kept out of sight of other horses might also cause loss of condition, and it is not uncommon for horses to lose weight after a long journey or moving yards. There is an increasing amount of evidence linking stress and Equine Glandular Gastric Disease (EGGD) (Sykes et al, 2019), which highlights the importance of maintaining a calm environment for your horse as much as possible. This can include ensuring continuity of human carers and reviewing any practices on the yard that may be distressing for them.

If the weight loss is very sudden or out of character for your horse, then the issue should always be discussed with your vet to try and determine the cause. However, if there are no underlying problems that need to be treated or managed, you might need to review their feeding regime to help support their weight and condition.

Feeding horses for weight gain

When feeding horses for weight gain, it is important to keep in mind that calories and energy are the same thing, with calories representing a measurement of energy. As humans we tend to use the term ‘calories’ when talking about weight gain and loss, but essentially if we consume more energy than we use, this will result in weight gain, and the same applies in horses.

Grazing

The horse’s grazing and forage intake is usually the best place to start when reviewing the ration. Good grazing provides the most digestible source of fibre, and in the spring this can provide more than double the energy requirements of a horse in light work. Grass is usually a highly palatable fibre source, and many horses will generally be happier when out in the paddock. However this is not always the case, so monitor your own horse’s behaviour to check they don’t appear to be distressed or fence walking (and not eating) when out in the field.

Some yards are lucky enough to have an unlimited supply of grass but if that’s not the case then alternative sources of conserved forages may be needed at times when grass availability and quality is reduced, or in inclement weather conditions such as frost and snow. If you are providing supplementary hay or haylage in the field, ensure that the supply is not being monopolised by more dominant members of the herd and that your horse is able to access it freely. Using smaller piles placed around the field may be required in this instance if the horses are not able to be separated.

Forage

The type and amount of forage provided is also an important factor to consider when it comes to weight gain for horses. Forage makes up at least half of most horse’s rations and so if it is of poor nutritional quality, it will have a significant impact on the horse’s condition. Forage quality is largely determined by how digestible it is – there are different types of fibre found in feeds, ranging from the very digestible pectin to the less digestible cellulose. High levels of lignin, an indigestible substance that gives a plant structure, will significantly reduce the digestibility of a forage. The older and taller a plant gets, the more lignin is present, which is why later cut hays will tend to be less conditioning than earlier cuts. Earlier cuts will typically be softer and leafier, and therefore more digestible and better for weight gain in horses.

Generally speaking, haylage or wrapped hay tends to be cut earlier than hay which is why horses tend to do better on it. However this is not always the case, and a very soft, early cut of hay may end up being better for weight gain than a haylage, so it’s important to assess what you have available. More information on the differences between hay and haylage can be found here.

How much should my horse be eating?

In most cases there is no reason to restrict forage for poor doers. This means it should be fed to appetite, so they always have plenty available. The greater the contribution the forage makes to supplying your horse’s energy requirement, the less bucket feed you should need to use, which is better for their digestive health and usually the most cost-effective way to feed.

Even when plenty of forage is provided, some horses may still not eat enough. For the underweight horse, it can be helpful to weigh how much hay is provided and then weigh what is left at the end of the day so that you can monitor what has been consumed. As a guide, a horse with no access to grass should ideally be consuming a minimum of 1.5% of their bodyweight of forage on a dry matter basis per day, though for horses fed free access forage we would expect an intake of closer to 2% of their bodyweight on a dry matter basis. For a 500kg horse, this would equate to 7.5-10kg per day.

However, all forages naturally contain some water which essentially ‘dilutes’ the amount of fibre being provided – different forages will vary but generally hay will have a dry matter content of around 85% and haylage will be lower at around 65%. Wrapped hay is usually somewhere in between at around 80% dry matter. If you have a regular supply of forage, it is possible to have it analysed to assess its dry matter content, but if this is not possible then the figures above are a good place to start. To calculate how much forage your horse should be consuming, simply divide the amount of dry matter required by 0.85 if you are feeding hay, or 0.65 if you are feeding haylage.

To illustrate the importance of knowing the dry matter of a forage, the following table shows the different quantities required of each forage type to provide 10kg of dry matter:

If your horse isn’t eating enough, consider the quality of the forage. Ensure it is clean and free from mould and dust – if other horses on the yard are also not keen then this could indicate a problem with the forage and so you may need to look at an alternative source. Earlier cut, softer forages will not only provide more calories but are also often more palatable, meaning that your horse may be inclined to consume it in greater quantities which is also advantageous when it comes to weight gain. Haylage or steamed hay can sometimes be more palatable than dry hay so these are other options to consider for the poor doer. More information on feeding the fussy horse can be found here.

The importance of good dentition

It is also important to bear in mind that a reduced appetite for forage can alternatively indicate a problem with chewing. Since chewing is the first stage of digestion, dental problems can have a big impact on your horse’s ability to digest their feed and forage. Having difficulty chewing is no longer an issue confined to older horses, and diastemata (gaps between the teeth) seem to be an increasing issue for horses of all ages. Regular checks by a vet or qualified dental technician are therefore really important.

If a horse is struggling, it’s important to find a format of fibre they can manage – short chops and mashes may be needed to ensure they consume enough. In a Dengie funded study, horses with poor dentition consumed about two-thirds less hay than horses with normal teeth. To put this into perspective, if a horse consumed 2kg rather than 6kg of an average hay, their energy intake could be around 40 MJ lower every day – it’s therefore not a surprise that horses with poor dentition can lose weight very easily. However, the horses with poor teeth in the study were able to consume the same amount of a soaked mash product – in this case, Dengie Alfa-Beet. In most situations, providing fibre in a form the horse can chew is all that is needed to promote weight gain. More information on forage replacers for horses can be found here.

Bucket feed

Once you have ensured your horse is consuming sufficient quantities of good quality forage, the next step is to look at the bucket feed. Feeds which are low in starch are a preferable choice to support digestive health. This is because horses produce comparatively low levels of amylase (the enzyme which digests starch) compared to other animals, and so the digestive system has a limited capacity to utilise starch. Starch is found in high levels in cereals, and excessive quantities of these cause a more rapid transit through the digestive tract which can result in starch reaching the hind gut, where it can cause problems. More information on the equine digestive system can be found here.

As an alternative to using feeds based on cereals, calories in your horse’s diet can instead be supplied through feeds that are high in fibre and oil. In particular, ingredients such as sugar beet and alfalfa are naturally higher calorie sources of easily digestible fibre and so can be beneficial for the poor doer. When researching horse feeds for weight gain, look at the energy value of the feed. There is no legal requirement to put this on the bag, but most suppliers do include it, as it provides a guide to how conditioning a feed will be. If it isn’t on the bag or the feed company’s website, the manufacturer should be able to provide it for you upon request. As a guide, feeds with a higher Digestible Energy (DE) content of around 11-12MJ/kg or more will usually be suitable for horses needing to gain weight.

If using a nutritionally balanced feed, it is important to ensure that it is fed to manufacturer’s recommendations to provide a balanced diet. For other feed types or if you are feeding less than the recommended amount, a broad-spectrum vitamin and mineral supplement or balancer should be included alongside. More information on feeding a balanced diet can be found here.

Meal sizes

Meal sizes are also an important factor to think about when feeding for weight gain. The horse’s stomach is relatively small for the size of their body and, with its structure being fairly rigid, it cannot stretch to accommodate a large meal. This means that feeding very large, higher starch meals in one go can lead to the feeds being pushed through the digestive system much more quickly, with the result that they are not able to absorb the full benefits of the feed. Therefore feeding smaller, more frequent meals can help the horse to get the most out of their feed and support weight and condition. The only exception here is in the case of highly fibrous feeds like chopped fibres which are digested in the hind gut. This means we can think of them like hay, so there’s no need to limit the meal size of these feed types, in contrast to cereal-based feeds. To keep meal sizes manageable, it can be useful to leave separate buckets of higher energy fibre feeds like sugar beet, alfalfa or dried grass products in the stable or paddock for the poor doer to trickle feed on through the day as another method of increasing their calorie intake.

Feeding the fizzy poor doer

When feeding the fizzy or excitable horse, many owners may struggle to find the balance between supplying enough calories/energy in the diet to maintain their horse’s weight and condition whilst managing their temperament. In these situations, it’s important to remember that feed cannot change a horse’s natural personality, but the choice of energy sources in the ration can influence behaviour. A study funded by Dengie in 2015 showed that horses fed diets high in fibre and oil were less reactive to novel stimuli and had lower resting heart rates than horses fed cereal-based feeds with the same energy/calorie value (Bulmer et al, 2015). This suggests that using higher energy fibre feeds is preferable to traditional high starch conditioning feeds when it comes to weight gain, especially for horses who are naturally sharp and excitable.

Hind gut health

The link between diet, the microbiome in the horse’s hind gut and overall health is increasingly being researched and understood. The horse’s colon is lined with mucus, and this offers protection to the colonocytes (gut cells). Fibre provides the specific type of energy that the colonocytes use and so feeding sufficient fibre can help to maintain a healthy gut lining. Studies have shown that when there isn’t enough fibre, bacteria will utilise the mucus to a greater extent as a source of nutrients and this can start to erode the mucus layer (Desai et al., 2016). This leaves the gut more vulnerable to acidity which compromises the joins between cells; a phenomenon known as leaky gut syndrome. If the gut is leakier or more permeable, it means pathogens and substances that wouldn’t normally escape from the gut into the body can now do so, which can lead to poor health or disease. Since infection or disease can result in weight loss, this further demonstrates the importance of fibre not only for providing calories but also for the support of gut health when it comes to improving weight and condition.

If gut health is compromised and harmful bacteria attack the gut, an inflammatory reaction occurs. The symptoms can include loose droppings, diarrhoea and possibly free faecal water. A high fibre diet is the starting point in trying to maintain a healthy gut and avoiding these issues but for horses prone to digestive upsets, the use of a digestive aid supplement containing ingredients like scFOS prebiotics, yeast or postbiotics can be of benefit. These have been shown to aid the health of the digestive system as well as improving fibre digestion by helping to establish a healthy population of microbes in the gut.

Feeding for top line

To develop top line in horses, they require the building blocks of muscle (amino acids) to be supplied in the diet, combined with working correctly for the muscles to build strength and increase in size. Horses will obtain protein from a variety of sources including grass, forage and the bucket feed. However, it is not only the amount of protein that is important, with the protein ‘quality’ being just as relevant. Protein is made up of amino acids, some of which the horse cannot synthesise themselves and so need to come from the diet. These are called essential amino acids. Of these, lysine is particularly important as it is a limiting amino acid – if the horse has insufficient lysine in the ration, then protein synthesis and therefore muscle development will be limited. Protein sources that contain a higher proportion of essential amino acids are generally considered to be of better quality.

Horse owners are often frightened of protein which is because it has historically been thought to cause a range of issues, which research has now shown not to be the case. Grazing and forage can go a long way to meeting a horse’s protein requirements, but to help ensure they are getting what they need, make sure you are using a feed appropriate for your horse’s workload at the recommended quantity. Good quality pelleted feed balancers are an excellent way provide the horse with vitamins, minerals and essential amino acids including lysine, especially for good doers on restricted forage rations. For poor doers, consuming the recommended amount of a fortified feed that is suitable for the horse’s level of work should supply what they need, alongside sufficient forage. Alfalfa is another great source of quality protein which means that relative to other fibre types, it contains good levels of the essential amino acids that are most valuable to the horse. This means that chopped or pelleted alfalfa can be a useful addition to top up a horse’s intake of quality protein without having to turn to costly protein supplements. More information on protein for horses can be found here.

Monitoring your horse’s progress

Measuring and assessing your horse regularly is important for spotting changes early so you can address any problems quickly. If you have made changes and still aren’t seeing any improvements after 2 to 3 weeks then you should review again and consider seeking help from a professional if there are no signs of improvement after a month. It is really important to ensure you have addressed any underlying causes as whatever changes you make to the diet, they are unlikely to have the desired effect if other contributing factors are still present. 

Seeking help and support

If you are struggling to achieve weight gain in your horse then contact an equine nutritionist who will help you to establish that the diet is appropriate and whether therefore, your horse should be gaining weight. They may suggest carrying out a forage analysis assessment to determine whether a change of forage might help and will talk you through various things you can try. There are some factors such as PPID that need to be managed with extra care when trying to keep weight on an older horse, and an equine nutritionist can advise how to do that as safely as possible.

Summary

• Consider the possible reasons as to why your horse may have lost weight – if the weight loss is sudden or without an obvious cause then consult with your vet in case there is an underlying issue.
• Provide access to good quality grazing where possible, if appropriate for your horse.
• Select an early cut, soft forage and feed it to appetite.
• Monitor forage intake and top up with easy-to-chew forage replacement feeds where necessary.
• Choose a bucket feed containing highly digestible fibre and oil that is low in starch to best support gut health.
• Feed little and often, especially if using cereal-based feeds.
• Use digestive aids to support fibre digestion and gut health.

References

• Sykes, B.W., Bowen, M., Habershon‐Butcher, J.L., Green, M. and Hallowell, G.D. (2019) Management factors and clinical implications of glandular and squamous gastric disease in horses. Journal of Veterinary Internal Medicine, 33(1), pp.233-240.
• Bulmer, L., McBride, S., Williams, K. and Murray, J.A. (2015) The effects of a high-starch or high-fibre diet on equine reactivity and handling behaviour. Applied Animal Behaviour Science, 165, pp.95-102.
• Desai, M.S., Seekatz, A.M., Koropatkin, N.M., Kamada, N., Hickey, C.A., Wolter, M., Pudlo, N.A., Kitamoto, S., Terrapon, N., Muller, A. and Young, V.B. (2016). A dietary fiber-deprived gut microbiota degrades the colonic mucus barrier and enhances pathogen susceptibility. Cell, 167(5), pp.1339-1353.