Equine Metabolic Syndrome (EMS): Is it just another label?

EMS or just an incredibly good doer?

An increasing number of horse owners are contacting me for advice regarding Equine Metabolic Syndrome (EMS); a condition which seems widely open to confusion or misinterpretation. So, what is EMS and what does it or should really mean when it comes to feeding our horses?

The term EMS was first adopted in 2002 after some similarities were drawn between horses and the human ‘metabolic syndrome’. In humans, metabolic syndrome is a set of diagnostic criteria that identifies individuals at high risk of disease associated with Insulin Resistance, primarily type 2 diabetes and cardiovascular disease. In horses, EMS is defined as the collective presentation of 1) insulin resistance 2) obesity or regional adiposity (fat) 3) previous or current laminitis. However since first adopted, the term EMS and the criteria for its diagnosis has often caused confusion, which may explain why it seems open to overuse and misinterpretation. There seems to be some agreement that this syndrome has yet to be rigorously defined and that currently, there is no widely accepted definition or set of clinical diagnostic criteria.

EMS is not a disease and is considerably different to the human metabolic syndrome. Despite popular belief diabetes in horses is extremely rare and is likely that there have only been a handful of genuine cases to date. Horses and ponies that have not had, or that are not currently suffering from laminitis, do not fit in with the current criteria for EMS and therefore should not be described as such. In addition, not all laminitics have EMS and this syndrome should not be automatically used as an ‘excuse’ or ‘explanation’ for obesity. There is a concern amongst some that overuse of the term EMS may mean that the true cause or risks of obesity and laminitis could be overlooked. EMS cannot be confirmed without comprehensive veterinary diagnosis and more research into this area is still required. In fact, some nutritionists question whether the term EMS should be used at all at this stage; feeling that the limited research and confusion surrounding this ‘syndrome’ may lead to excessively restrictive or liberal management depending on whether or not EMS is ‘diagnosed’ when in fact, focus should be on identifying and managing the risk factors associated with laminitis.

Nutritional management of EMS, as with any laminitis prone animal should focus on:

·         Providing a diet low in non-structural carbohydrate (NSC – starch, sugar and fructan)

·         Restricting or possibly removing grazing

·         Feeding soaked hay (12-16 hours & ideally in tepid water) or a low calorie hay replacer approved by The Laminitis Trust. Alternatively, consider having your forage analysed

·         Managing weight – aim for a body condition score of 5 out of 9 and remember that it is normal and perfectly healthy for ponies/ natives to lose some weight over the winter before the arrival of better grass in the spring

·         Maintaining regular exercise programme

·         Providing a balanced diet, including suitable levels of vitamins, minerals and quality protein – a feed balancer is the ideal way to provide a balanced diet without excess calories

·         Providing enough fibre – do not restrict forage to less than 1.5% of bodyweight (7.5kg per day for a 500kg horse) unless under veterinary supervision

Laminitis is a serious condition, the risk or occurrence of which should certainly not be taken lightly. However, is simply being able to understand, identify and manage the risk factors associated with laminitis more important and potentially safer than imposing a label of EMS? Some would agree so.

Bran benefits

Bran, often in the form of bran mash, has long been fed to horses as a source of fibre or laxative to help prevent colic, as a warm and palatable feed for sick horses or those with poor teeth and after a hard days hunting. However, should these feeding practices be considered as words from the wise or an outdated tradition?

One of the biggest problems associated with feeding bran is its very high phosphorus content. The ratio of calcium to phosphorus in the horse’s diet should be ideally maintained at 1.5-2:1 (1.5-2 times more calcium than phosphorus) but in comparison, bran contains 10-12 times more phosphorous than calcium. High levels of phosphorus decrease calcium absorption, resulting in deficiency. Consequently, calcium is drawn from bones (where 99% of calcium is stored) which in serious cases, causes them to weaken. Although far less common now, feeding large amounts of bran and consequently high levels of phosphorus, can result in ‘Millers Disease’ (Nutritional Secondary Hyperparathyroidism); a condition which eventually results thickening and distortion of bones caused  by lost minerals being replaced with fibrous tissue.

Feeding small amounts of bran on an infrequent basis will not cause major mineral imbalances, but as we all seem to appreciate that new feeds should be introduced gradually, why make an exception for bran? In fact, some researchers believe that this could have a negative effect on the hindgut microbes responsible for fibre digestion. Research has also shown than bran does not act as laxative, regardless of whether it is fed wet or dry. Instead, any ‘laxative effect’ is likely to be the caused by the mild disturbance or irritation resulting from the sudden introduction of a new feed.

For people, fibre (including bran) can increase the bulk of stools by helping them to retain more water and consequently make them easier to pass. However, fibre requirements in horses are much higher and whilst bran does contain fibre, the content is much lower (10-12%) than in sugar beet (20% - unmolassed) and hay.  In fact even as a source of water, the benefits of a bran mash may be questionable when you consider the small amount of water actually consumed in comparison to the horse’s daily requirements.

Many of us reach for a mug of hot chocolate or soup in colder weather and whilst a feeding a warm bran mash may be a comforting thought, it will not continue to keep your horse warm after he has eaten it.  As a result of fermentation in the large intestine, the digestion of hay and other forages produces heat (regardless of the weather) and therefore nutritionally, feeding additional hay is more likely to help keep your horse warm.

Whilst feeding bran will not always result in serious harm, particularly if properly balanced and fed in small amounts to adult horses; reported benefits are based largely on tradition. Consider whether adding bran to your horse’s diet is really necessary as unfortunately, it is one feeding tradition that may potentially cause more harm than good.

Electrolytes: What are they and does your horse need them?

Electrolytes are mineral salts which, when dissolved in water, become electrically charged particles called ions. However, whilst scientifically accurate, this explanation offers little help to many horse owners when it comes assessing their horse’s need for electrolytes.

When horses sweat they lose electrolytes, the main ones being sodium, potassium, chloride, calcium and magnesium (although calcium and magnesium are lost in smaller amounts). Sweating rates can be as high as 10-15 litres of sweat per hour, with electrolyte losses of approximately 10g/ litre.  Electrolytes are important for many cell functions including muscle contractions and the transmission of nerve impulses. A lack or imbalance of electrolytes can affect almost every physiological system in the horse's body and result in conditions such as heat stress, fatigue, synchronous diaphragmatic flutter (thumps) and tying up. Electrolytes control the direction of water in the body and maintain fluid balance. The body needs electrolytes to retain water which is why you may have read that it is more difficult to rehydrate by drinking water alone.

However, the amount of electrolytes lost is proportionate to the amount the horse sweats and consequently, free access to a salt lick and plenty of forage (hay provides potassium) is more than sufficient for many leisure horses and those in light work. In fact, most losses would gradually be replaced over time, simply by the horse eating and drinking normally. However for horses sweating heavily and on a on a regular basis, a water and electrolyte solution will aid a more rapid and effective recovery.  Regardless of this, it is not possible to replace total losses in one feed/ solution. Such supplements aim to support hydration and the replenishment of electrolytes but in fact, it will take several days for levels to be fully restored following heavy and prolonged sweating. Whilst it is not possible to ‘preload’ electrolytes, maintaining hydration and electrolyte balancer prior to exercise/ competition is an important precaution, helping to reduce the risk of conditions such as tying up.

Table salt (sodium chloride) and in heavier work a combination of table salt and Lo Salt (potassium chloride and sodium chloride at a 2:1 ratio), can be a cheap and effective form of electrolyte replacement, either added to horses feed or diluted in water. Water must be available if adding salt directly to the feed and must also be offered as alternative to horses that refuse to drink the salt and water solution (this is also the case if using commercial supplements). Apple juice has been recommended by many as an effective flavouring but horses should be ‘taught’ or accustomed to drink the flavoured water before salts are added.

Although more expensive, commercial electrolyte supplements can be beneficial, despite speculations that some contain little more than sugar.  Whilst we now know that horses do not need high levels of sugar in order to absorb electrolytes, ingredients such as dextrose and sucrose are often still included to help make supplements palatable and provided that they also contain appropriate levels of electrolytes, this is not a problem. Look for supplements containing sodium, potassium, chloride and ideally magnesium and calcium too. Sodium and potassium should feature near the top of the list of ingredients, with sodium provided in the largest quantity. For competition horses, also take care to ensure that any supplement used does not contravene FEI rules and is covered under the UFAS BETA NOPS code.

Electrolytes are undoubtedly important, but it is easy for such a scientifically complex subject to cause confusion. If you think your horse may need additional electrolytes, ask a nutritionist for advice on adding salt to his feed, or look for a supplement manufactured by a reputable company. Such companies should have a nutritionist available to clearly explain the benefits of their product, what’s in it and how to use it safely.

Seaweed: A word of caution

Seaweed supplements have long been fed to horses and perhaps you feed or have fed a seaweed supplement to one of your own horses? Seaweed is often promoted as being an effective broad spectrum vitamin and mineral supplement, a good source of amino acids and a beneficial joint supplement. However, due to the potentially high iodine content, feeding seaweed could have harmful effects.

Iodine is one of 8 ‘micro minerals’ which by definition, means it is needed in very small amounts by the horse. Although only needed in small amounts, iodine is essential for the production of thyroxine and tri-iodothyronine (thyroid hormones), which influence numerous aspects of horse health including metabolism, heat regulation and bone development. However, iodine is one of the few minerals that can be harmful when oversupplied and for which intolerable levels can be reached relatively easily.

Iodine toxicity is more common than deficiency and in most cases, is the result of over feeding high iodine supplements such as seaweed. Even for horses without access to grazing, the recommend ration of compound feed, broad spectrum vitamin and mineral supplement or balancer should easily meet the horse’s iodine requirements without the need for additional supplementation. In fact, because all of the vitamins, minerals and amino acids are naturally occurring (and the levels at which some are provided), a seaweed supplement alone will not provide a balanced diet. In addition, there is no scientific evidence to suggest that seaweed is beneficial joint supplement.

It is estimated that a 500kg horse needs 1-2mg of iodine per day, with the National Research Council (NRC – the accepted institute for standardising animal diets) setting toxic levels at 50mg per day (or 62.5mg for very hard working horses). However, some nutritionists believe that ‘undesirable effects’ or even toxicity can be reached at much lower levels.

Seaweed supplements may typically contain around 835mg of iodine per kilogram and may be recommended at a rate of 50-150g per day for a 500kg horse (iodine levels and recommended rations of seaweed do vary between suppliers). Based on these figures, owners could be providing 42-125mg of iodine per day from seaweed alone. Whilst not all companies selling seaweed recommend rations containing toxic levels of iodine, some nutritionists question whether it is ‘good for horses’ to be oversupplied with a nutrient required in such small amounts.

Excess iodine poses greatest risk to pregnant mares, potentially causing infertility, abortion and due to the high concentration on iodine in the placenta and milk, weakness and goiter (swelling of the thyroid gland) in foals. In non-pregnant, adult horses, iodine toxicity can cause hypothyroidism; a condition which affects thyroid function/ hormone production and can result in  goiter, obesity, poor coat condition, lethargy and intolerance to cold.

Seaweed can be fed safely to horses and may have some benefits to offer. However, if you are using a seaweed supplement, first and foremost establish whether or not you reaching toxic levels of iodine (a nutritionist will be able to offer advice on this) and if the answer is yes; remove or reduce your supplement and never provide ‘free access’ or ‘ad-lib’ seaweed.. If not, it may still be worth asking yourself whether you are oversupplying iodine unnecessarily and if any benefits of feeding seaweed could be achieved more appropriately.

Molasses Myths

Molasses seems to have become somewhat of a swear word and during the last year, the number of enquiries that I receive about molasses certainly seems to be increasing. So, what is the truth about molasses and should we really be fearful of it?

Molasses is a by-product taken from the refining of sugar beet or sugar cane and contrary to popular belief, contains approximately 55% sugar. Molasses or alternatives such as Molaferm and Molgo (made from a blend of molasses and oil) are used by the majority of feed manufactures and therefore very few feeds are molasses free. However, this does not automatically deem feeds ‘unsafe’ or ‘unnatural’ as commonly thought.

Many people fear that sugar is unnatural to the horse but in fact, this couldn’t be further from the truth. Horses evolved to consume a forage only diet and therefore are well adapted to digesting and absorbing sugar. In fact, the sugar in molasses is largely sucrose, the same sugar found in grass! Horses cannot be ‘allergic’ to sugar and all horses, even those prone to conditions such as laminitis, need some sugar to stay healthy (see previous blogs on allergies and sugar). Having said this, problems can occur when overweight, under-exercised horses/ ponies are fed high levels of sugar and there are undoubtedly some that need a low sugar diet. However, this doesn’t automatically mean that feeds containing molasses are unsuitable.

Firstly, ‘molasses free’ does not mean sugar free and feeds containing molasses are not automatically high in sugar. If your horse needs to be on low sugar diet it is the total amount of sugar in the diet and not just the inclusion of individual ingredients such as molasses that should be of concern. In fact, many feeds suitable for laminitics and excitable horses do contain some molasses. Molasses or molasses and oil blends are typically added at 5-10% and therefore may contribute as little as 2% sugar. In total, mixes, cubes and chaffs typically contain 4-6% sugar and when you consider the quantities, in which they are eaten in comparison to forage, actually account for a very small proportion of the total sugar consumed. In fact, forage is the largest contributor sugar in the horses’ diet (including hay) and a 500kg horse living out at grass can easily consume up to 1.9kg of sugar per day from glass alone (compared to approximately 120-180g in 3kg of ‘hard’ feed).

The term ‘everything in moderation’ is often accepted as good advice for humans and in the case of molasses, is perhaps something that should be applied to our horses. In truth, the facts often do not justify the fears and molasses is certainly not something that must be avoided at all costs.

Feeding Sugar Beet – The Facts

Sugar beet has long been fed to horses, but trying to separate the myths and misconceptions from the facts, can often make the decision of whether or not to feed sugar beet a confusing decision. So what is sugar beet and what can we, or should we, really be using it for?

Sugar beet is a root vegetable, the root of which is high in sucrose (table sugar). The sugar beet pulp we feed to our horses is the by-product of sugar beet processing which provides the sugar to put in our tea!

Sugar beet is high in fibre but in low starch and sugar (if unmolassed- approximately 5%) and therefore is a safe, easily digested and non-heating feed. For laminitics, look for varieties approved by The Laminitis Trust. Sugar beet is also high in calcium and low in phosphorus (which is ideal for horses) and being rich in branch chain amino acids, can be a useful feed for horses with liver damage.  Sugar beet must always be soaked before feeding (10 minutes – 24 hours depending on the variety) so as not to cause choke or colic.

Although high in calories (up to 13 MJ/ DE/ kg depending on the variety) and commonly fed for weight gain, sugar beet contains approximately 80% water once soaked and therefore is of very little nutritional value unless fed in large amounts (nutrients are diluted in water). This considered, sugar beet is often not fed in large enough quantities to provide a significant level of calories. A scoop of soaked sugar beet weighing 1kg, actually equates to only 200g of feed (approximately). For good-doers this is of course ideal as once soaked,  only a small cupful will go a long way, helping to add ‘bulk’ without excess calories. The motto of the story here is to weigh your sugar beet before you soak it!

 

Being high in digestible fibre, sugar beet can also be fed as partial hay replacer for horses and ponies with poor teeth but again, take care to weigh it before soaking to ensure that you are providing enough fibre!

Used correctly, sugar beet can be a useful and versatile feed but like any other, must be understood if we are to see the benefits. Will you be feeding sugar beet this winter?

16 years young...



"I'm as young as I feel"



We all want to do the best for our horses as they get older, but when is the ‘right time’ to move to a senior feed? In truth, there is no definitive answer as like people, horse’s age at different rates.  In the past horses at 16 were sometimes described as ‘veterans’ however nowadays with suitable management many horses continue to live healthy and active lives well into their twenties or even thirties! 

Not all horses struggle to maintain condition as they get older, so it is important to choose feeds containing an appropriate level of energy (energy = calories). For those able to maintain weight well on forage alone, a balancer specifically formulated to meet the needs of senior horses, is the ideal way to ensure optimum nutrition without excess calories.

With age and previous worm damage, digestion and absorption of nutrients may be less efficient. A high fibre diet is essential for maintaining digestive health and constant access to water helps to prevent impaction colic. Some horses may also benefit from additional digestive support in the form of pro/ prebiotics. Feeds high in antioxidants, particularly vitamins C and E, provide respiratory and immune support.

Quality protein is important for helping to maintain muscle tone and topline but again, protein digestion may be less efficient in older horses. As a guide, look for feeds containing 12-14% protein (for compounds feeds – balancers will be higher than this). Stiffness and arthritis (to varying degrees), are common in older horses and some may benefit from feeds or supplements containing additives such as glucosamine.

Teeth can become a problem for many older horses and should be checked regularly (every six months). If not addressed, difficulties in chewing can lead to conditions such as choke, colic and weight loss. Look for mixes containing smaller pellets or where necessary, feeds/ cubes that can be soaked to make a mash. Remember that this may need to include a full replacer, either in the form of soaked cubes or short chopped fibre feeds.

Horses and ponies with Cushing’s disease need the same, careful nutritional management as a laminitic; regardless of whether or not they are on medication or have previously suffered from laminitis. In practise, this means providing a diet that is high in fibre and low in starch (found in cereals), sugar and fructans (found in grass). If your senior horse has Cushing’s, or is prone to conditions such as colic or tying up; avoid mixes and seek advice from a nutritionist. Remember that the most suitable diet may include feeds that do not say ‘senior’ on the bag.

Whilst the ageing process is inevitable, nutrition can play an important role in supporting senior horses whether they are in work or enjoying retirement. How many years ‘young’ is your horse?