What is EMS in horses?

Horses are beautiful and sensitive creatures but they can be susceptible to a wide range of health conditions that severely affect their enjoyment of life. One such condition is equine metabolic syndrome (EMS). If you’ve ever wondered if your horse might be at risk of EMS then we’ve got a go-to guide just right for you.

Learn all about EMS here and find out how you can give your horse the extra support they need to stay healthy. With the right information, the right horse insurance and early diagnosis, you should be able to look forward to many happy years together.

Full of all the information you need, this guide is essential reading for anyone worried about their equine friend falling victim to EMS. As well as in-depth guidance on warning signs, diagnosis, and treatment we’ve also included advice on how to prevent EMS in the first place.

Alongside horse insurance cover, is there any better way to stay on top of such a serious health condition?

Contents

• Chapter 1: What is Equine Metabolic Syndrome?
• Chapter 2: How do I know if my horse is at risk of EMS?
• Chapter 3: Spotting the signs of EMS
• Chapter 4: Acting fast to get an early diagnosis
• Chapter 5: Treatment and management plans just right for your equine friend
• Chapter 6: Preventing EMS in the first place
• Chapter 7: Top tips to keep your horse’s weight healthy

Chapter 1: What is Equine Metabolic Syndrome?

EMS isn’t a disease, instead it’s a hormonal disorder in equines quite similar to Type 2 diabetes in humans. It tends to be characterised by three specific issues:

1. Insulin resistance - Horses and ponies with EMS become insensitive to the hormone insulin. This leads to two things. First, they have difficulty controlling their blood sugar (glucose) levels. And second, they have high circulating levels of insulin in the blood.
2. Obesity or abnormal fatty deposits - Horses and ponies that are overweight are more likely to be experiencing EMS. But that doesn’t mean all horses with EMS are obviously overweight. Some only have abnormal body fat deposits. For example, a ‘cresty’ neck, fat pads behind the shoulder, or fat around the eye sockets.
3. Laminitis - A common indicator that a horse is suffering from EMS is mild recurrent laminitis, with no obvious cause. However, as with being overweight, just because your horse has laminitis doesn’t necessarily mean it has EMS.

As you would expect, your vet will need to take into account your horse’s history and run a series of tests before making any diagnosis of EMS. One of the many benefits of horse insurance is you can seek professional assistance early before the problem gets worse.

Be aware that EMS can manifest itself in a variety of different ways, so having professional help is vital. Research into EMS is ongoing, and scientists are currently exploring the possibility that there are several different sub-varieties of EMS affecting equines.

Chapter 2: How do I know if my horse is at risk of EMS?

EMS often develops slowly over time so it can be difficult for owners and even professionals to spot. At the heart of the disorder is the hormone insulin. In a healthy horse, insulin acts to regulate blood sugar levels. It does this by taking glucose (sugar) from the bloodstream and using it as fuel (for example, for muscles) or storing it as fat.

However, EMS begins when hormones produced by excess fat cells in the body prevent insulin from performing this function. This eventually leads to insulin resistance and then elevated blood sugar levels. Ultimately this leads to the production and release of yet more insulin.

While it isn’t yet understood quite how this happens, these hormonal changes can affect normal blood flow and pressure in the hoof. This increases the risk of laminitis and other complex disorders.

It’s believed that any horse or pony is at risk, although some breeds and types seem to be more prone to it. Particularly those horses bred to survive in harsh climates such as Welsh, Dartmoor and Shetland Ponies, and Morgan, Arabian and Warmblood horses.

The reason seems to be that these breeds use glucose very efficiently to ensure they have plenty of energy reserves for when food becomes scarce. However, when these breeds are placed in an environment where they can consume too many calories and don’t get as much exercise as they would naturally, they can become overweight and develop EMS.

Indeed a recent study by researchers at the University of Liverpool focusing on north west England and north Wales found that EMS is widespread among Britain’s native ponies and cobs. As well as obesity, EMS risk factors included age, being female, a more sedentary main activity (such as showing, or being a companion animal), and shorter periods turned out on summer grass.

Chapter 3: Spotting the signs of EMS

There are a range of different signs that horses and ponies could show if they’re suffering from EMS. Being well-informed about these symptoms is the best way to get help quickly. We’ve listed below all the warning signs that an owner needs to look out for that could indicate a horse with EMS.

Unfortunately, it’s all too easy to attribute these signs to just getting older. If you’ve got horse insurance cover for your faithful friend then make sure you use it to investigate any of these potential giveaways.

• Development of abnormal fat deposits. Perhaps the most common early signs of EMS. These are pockets, bulges or pads of fat, usually seen around the crest, behind the shoulder, the rump (particularly towards the tail head) and over or around the eyes. If your horse is already overweight then these could be more difficult to spot.
• Difficulty losing weight. If you notice your horse putting on weight then you might decide to change their diet to keep them trim. If the weight isn’t shifting then don’t just put it down to age or temperament. It could be something more serious that needs investigating.
• Recurring episodes of acute laminitis. As already noted, EMS is a common underlying cause of laminitis in equines. Unfortunately, EMS may be present for a long while before the onset of laminitis. It’s therefore so important to recognise and treat the disease promptly to reduce the risk of the disease. Do you know how to spot lameness in your horse? If you’re unsure, then read up on it now!
• Increased drinking and urination. Yet another tricky-to-spot sign. After all, unless you’re with your horse 24/7 you won’t constantly be monitoring your horse’s drinking and/or urinating habits. An easier way to look for this is to keep an eye on how much bedding you are using to keep the stable dry. A sudden increase could be a clue that they’re urinating more. And try to keep track of how often you are needing to fill up their water trough.
• Lethargy (lack of energy). Healthy and happy horses are always on the move. So, a general lack of energy is a common early sign that something is not quite right. Again, though because EMS develops gradually over time this particular development can be difficult to spot. Be vigilant for signs of lethargy. For example, are they showing less enjoyment in playing with their field mates, or seem less interested in you or in the world around them? Never just put lethargy down to getting older and ignore it. Timely investigation of such issues is vital.
• According to the British Horse Society, EMS has also been associated with infertility in mares. You might not notice this as mares with EMS may still go in and out of ‘heat’ regularly. But it’s believed that their fertility, and ability to get in foal, may be reduced by EMS.

Chapter 4: Act fast to get an early diagnosis

Getting an early diagnosis of EMS and managing the disorder before laminitis develops is key to preventing chronic, recurrent laminitis. While you and your vet will be on the lookout for the clinical signs as discussed above, blood testing is often performed to determine whether a horse has EMS.

When a horse has EMS and becomes insulin-resistant, their body produces more insulin in order to counteract it. Samples will generally be needed to measure whether there are high levels of insulin and glucose in the bloodstream. If there are, this is a clear sign of EMS. If you’re worried about EMS, give your vet a call for further guidance on getting a diagnosis.

Be aware that some signs of EMS are very similar to Equine Cushing’s Disease. A blood test will help to determine which one your horse has. Blood tests and diagnostic processes can soon get expensive, that’s why it’s always worth having horse insurance for you to fall back on.

Chapter 5: Treatment and management plans just right for your equine friend

The good news is that while there isn’t a ‘cure’ for EMS, its effects can be successfully managed and even reversed. However, due to the complex nature of EMS, it will take a lot of hard work and it might feel at times that they’ll never lose the necessary weight.

For horse owners this can be a difficult experience, that’s why it’s so useful to have horse insurance to help with support from your vet, nutritionist, or even a professional coach. Successful management will require some real lifestyle changes and a plan tailored to meet their specific needs.

To reduce weight, improve insulin sensitivity and treat EMS requires a reduction in their calorie intake and an increase in physical activity. Exercise has been found to significantly improve the uptake of glucose by muscles and decrease blood sugar levels. But be careful of beginning an exercise routine that’s beyond their capabilities.

Unfortunately, a big difficulty if your horse has EMS is if they have acute or chronic active laminitis. This will affect how much exercise they can do. Any controlled exercise programme needs to be taken under veterinary advice and tailored to the individual animal. You and your vet will need to take into account the horse’s level of fitness, current condition, age and the facilities available to you.

Obviously if your horse gets injured when exercising then this can really set back your progress. Similar to arranging effective horse insurance, knowing how not to injure your horse is a key part of responsible equine ownership.

How successful management and treatment will be varies from horse to horse. Many horses respond well to management through diet and exercise. For others, further medical treatments might be necessary. A variety of medications and supplements are also available for horses suffering with EMS. However, these should only ever be used after seeking veterinary advice and together with other management techniques. Having access to the best medicine and treatment options is just one of the reasons why owners invest in horse insurance for their treasured equine.

Chapter 6: Preventing EMS in the first place

EMS is a complicated disorder we still don’t know everything about. While any horse or pony, regardless of their weight, can be affected, the condition is seen much more frequently in overweight horses. So, the risk of developing EMS significantly increases if your horse is overweight or obese.

So, a big way to stop EMS from ever developing is to keep your horse at a healthy weight in the first place. But can you recognise an overweight horse when you see one? It’s not as easy as you would think! Particularly among leisure horses and ponies, obesity is increasingly seen as a welfare crisis in the UK. Recent research has shown that just casting your eye over your horse is not an effective way to assess their condition. Indeed, when asked to identify overweight horses and ponies from a panel of 12 images only 11% of respondents correctly identified all six overweight animals. Why don’t you take a look and see how well you do?

So, how can you tell if your horse is keeping trim? The following are some important checks to make:

• Are the ribs visible or easily felt under the skin?
• There should be no, or only a minimal, crest.
• There shouldn’t be any fat parts over the shoulders or ribs.
• There shouldn’t be a gully between the horse’s hindquarters.

While these are great to check for when grooming, are there more precise ways to check on their weight? Well, yes there are.

Give your horse a body condition score

The perfect way to get hands-on when it comes to weight is to perform body condition scoring on your horse. The BHS has a number of useful articles on doing this effectively.

There are three key areas that you will need to look at. To help you determine whether your horse’s weight is down to muscle or fat, remember that fat will feel spongy whereas muscle is firmer. However, be aware that worrying crest fat can start to feel hard and become difficult to move from side to side.

The areas you need to consider are:

• Neck and shoulders
  First check the shape of the neck muscles and see whether there is thickening along the crest. Run your hand down the neck on to the shoulder. Check that the shoulder blades are clearly defined.
• Body
  Ideally you should be able to feel the ribs with just light pressure. Now place your hand on their back and feel for the spine. Look out for fat building up on either side of the spine and creating a gutter.
• Hindquarters
  Run your hands over the hindquarters and you should feel the hip bones easily under the skin. Taking extra care, look at your horse from behind. An apple shape and a gutter along the backbone suggests they’re overweight. Also feel for fatty areas around the base of the tail.

Using a scale of 0-5, score each of these three areas individually using the images and descriptions on the BHS fat scoring web page. For the majority of horses, a healthy fat covering is a score of 2.5 – 3 out of 5. It’s a good idea to body score your horse at the same time every week. Keep a record of their scores and take photos to help you spot any gradual changes.

Use a weighbridge

Having access to a weighbridge is very useful and you should try to weigh them once a month if possible. If your yard doesn’t have one, then perhaps ask your vet. 

Use a weigh tape

A useful addition to body scoring is to use a weight tape. While they’re no substitute for actually weighing your horse, they can alert you to an increase or decrease in weight.

Keep an eye on their cresty neck score

A cresty neck has been linked to an increased risk of laminitis and EMS. So, it’s well worth taking the BHS advice and performing this regularly.

Chapter 7: Top tips to keep your horse’s weight healthy

Obesity is the main known risk factor for developing EMS, so it’s important to keep your horse to a healthy weight throughout their life. Try out some of these tips to help shift any extra weight.

• Cut the calories
  Make a note of everything your horse is eating and add it all up – you’ll be surprised at how it can mount up if you’re not careful. Weighing your forage and feed, allows you to limit the intake of any unnecessary calories! You might also need to get your forage analysed so you know exactly what calories your horse is eating.
• Be strict with the treats
  Those who care for horses know how hard it is to resist giving their favourite equine a treat or two. But when it comes to losing weight you need to be strict. Make sure that everyone who’s caring for the horse is on board and won’t be handing out sneaky treats when your back is turned!
• Consider soaking your hay to reduce the calorie content
  It’s usually recommended to soak hay for at least six hours in cold water or one hour in warm water. You might also consider feeding a lower calorie forage. For example, adding barley straw to their hay can contribute to weight loss. However, only ever make such changes gradually.
• Slow down the eating process
  Use small-holed hay nets or double netting to increase the amount of time it takes your horse to eat their hay.
• Keep off the grass
  Grass can add a huge number of calories to a horse’s diet. If you don’t want to restrict them completely, you could try strip grazing or a grazing muzzle. Or perhaps turn your horse out at night, when sugar levels in grass are naturally lower. Be careful of simply limiting their time spent turned-out on grass. They might try to compensate by overeating!
• A woodchip paddock is ideal, if one is available
  For a horse suffering with EMS, it’s important that their calorie intake can be tightly controlled. However, it’s also important that horses are never left for long periods without food.
• Get them working out
  Horses need exercise to burn calories and stay healthy. Make sure to start off gradually and be sure to go at their speed. Stick to an even and consistent surface and carefully monitor for signs of laminitis. Even if your horse isn’t capable of being ridden, taking them on a daily walk is great exercise.
• Watch the rugging
  During colder times of the year try not to keep an overweight horse unnecessarily rugged. Instead of those extra calories being laid down as excess fat, the horse can instead use the calories to keep warm. Knowing when and when not to rug a horse is an important part of effective horse care.
• Keep things interesting
  Use trickle feeders or hay balls to help reduce the rate of consumption, whilst also making feeding more interesting. This will also provide some additional movement for the horse. We have discussed some more great enrichment ideas for your horse elsewhere on our site.

So that’s the ultimate go-to guide to EMS in horses. If you’re at all worried about your horse and EMS, then give your vet a call. Getting that immediate help and reassurance is why you arranged horse insurance in the first place, so you should use it. Let us know how you get on!

Policy benefits, features and discounts offered may very between insurance schemes or cover selected and are subject to underwriting criteria. Information contained within this article is accurate at the time of publishing but may be subject to change.