Ems

Equine Metabolic Syndrome -
Clare McKinstry, MRCVS
Here is a scenario many horse or pony owners may find familiar. I was presented with a pony cal ed “Alfie”. he is a much loved, 8 year old, Shetland pony gelding who has a previous history of mild to moderate episodes of laminitis. His companion “Snowy”, is also an 8 year old Shetland pony gelding but has had no previous episodes of laminitis. Neither “Alfie” or “Snowy” are obese, however “Alfie” is in good body condition, carrying a little extra weight,“Snowy” however is in lean body condition. They are both kept under a strict management regime where they are only turned out in a restricted paddock at night. Smal amounts of soaked hay is fed during the day, a veterinary prescribed product aimed to prevent grass induced laminitis is fed during the danger months ie spring / autumn in a smal , high fibre chaff meal once daily and their feet are trimmed by a remedial farrier every 5 -6 weeks. When they are stood in, they are both stood in a deep supportive bed of shavings. Despite all these precautionary and meticulous measures, “Alfie” has become laminitic again! Understandably “Alfie's” owners were both very distressed and frustrated and asked whether there was anything else they could do. Having examined “Alfie” and established he was in no immediate danger, I recommended that we take a blood sample to assess his insulin and glucose levels and in doing so, his laminitis risk. This involved “Alfie” having a blood sample taken first thing in the morning after he had been starved overnight. He was then fed a measured amount of glucose in a feed and a second blood sample was taken 2 hours later, this al ows enough time for the glucose to be absorbed from his gastro-intestinal tract into his blood stream. The results of the blood test revealed that “Alfie's” blood glucose and insulin were higher than normal, indicating that he was suffering from Equine metabolic syndrome (EMS), he was also flagged as an increased laminitis risk.
If you see any of the symptoms or suspect laminitis you should Cal your vet in al instances (we can advise you over the phone how to make your horse or pony more comfortable in the meantime). Bringing your horse into a stable onto deep shavings to support the feet and removing al hay and feed is best in the initial few hours until veterinary advice is obtained.
The potential clinical signs of EMS can include Laminitis (often unexplained), Obesity, Abnormal fat deposits (thickened, “cresty” neck, fat deposits above the eyes, behind the shoulders and at the tail head), “Good Doer” - Difficulty in weight loss, Lethargy, Excessive drinking + urination and final y Infertility Diagnosis:
Diagnosis is based on clinical examination and assessment of the
clinical signs. Various diagnostic blood tests are available but can be
affected by outside factors such as pain, stress (especial y if the pony is
laminitic), age and other il nesses to name but a few. A positive oral
glucose tolerance test as described above in the case of “Alfie” is
recognised as being strongly suggestive of EMS. It does however
involve starving the animal for 12 hours which can be distressing for
both the animal and the owners! The “Gold Standard” test is the
combined glucose-insulin tolerance test but it cannot be performed at
the yard. It requires hospitalisation and is very labour intensive. For this
reason the oral glucose tolerance test is most commonly used in
practice.
Since the condition of insulin resistance has been linked to obesity, by far the most important treatment for EMS is diet and exercise to reduce the animal's body fat.
This should be wel balanced, high in fibre and containing al essential minerals and vitamins whilst remaining low in soluble carbohydrates, for example, soaked hay with a low calorie feed balancer. Feeds to be avoided include grass, cereals, apples and carrots. Animals suffering from laminitis can also be supplemented with biotin, methionine, Vitamin E (8,000 – 10,000iu) and chromium.
Exercise is incredibly important in the treatment of EMS. It has been proven that exercise not only encourages weight loss, (particularly a reduction in omental fat) but also increases the uptake of glucose into the muscles thereby reducing blood glucose levels. It has been shown that a fit pony (even if a little overweight) wil have reduced insulin resistance and wil lose weight faster than an unfit pony. It is difficult to exercise ponies that are suffering from laminitis so in these cases we treat the laminitis first before embarking on an exercise program. We can also use medical therapy in these ponies, namely a drug cal ed Metformin.
Metformin is a human drug and is used to lower blood glucose by increasing the uptake of glucose from the blood into the muscles – very much the same action that exercise has. It is inexpensive and comes in tablet form that can be given in a feed twice daily. However, it should not be seen as a long term treatment and should be replaced with an exercise program as soon is it is safe to so.
A weight loss plan was instigated having established the fol owing factors: · The owners ful y recognised that “Alfie” needed to lose weight and their ful co-operation wil help towards achieving a successful result. · The feeding and daily management of “Alfie” was assessed. · “Alfie's” current workload and soundness for exercise assessed. · A realistic weight loss goal was decided upon with regular monitoring required. (Aim to lose 25 - 30 Kg in 4 - 6 weeks). · Al dietary changes must be made slowly and long periods of time where food is not available avoided. · · An appropriate weight maintenance program must be established once the target weight has been achieved. “ALFIE'S” TREATMENT PLAN · Al paddock turn out was stopped, even if restricted. · Al feeding of apples, carrots or cereal feed was stopped. · His sole diet consisted of mature hay or a hay substitute such as a high fibre chaff. The amount of hay to be fed in 24 hours is calculated by 1.5% of the pony's body weight. “Alfie” was 225Kg (using a weight tape), his ration of hay per day was 225Kg x 0.015 = 3.375Kg. (this can be soaked or dry) · This diet was balanced using a low calorie commercial feed balancer. · As “Alfie” loses weight, the ration is recalculated using the same method as above (daily hay ration = Body Weight x 0.015). Regular monitoring of weight loss is required. · (If less than 1% of body weight is fed, the pony may start to eat his own droppings, bedding and even affect his hind gut function.) · His hay was split into 4 rations / day. “Alfie” started to lose weight and responded wel to the treatment of his laminitis and has now started on an exercise program. From 10 minutes of walking in a menage three times a day, he has gradual y built up to 20 minutes three times a day and wil shortly start lungeing exercise introducing easy trot work. In time “Alfie” wil hopeful y reach his target weight and his blood glucose and insulin levels wil return to normal. At this point turn out in a restricted paddock wil be al owed, taking great care in times of danger such as spring and autumn or after rainfal , frost or drought. He wil continue to be exercised on a daily basis. Sadly, some equines wil not respond to treatment despite losing weight and wil remain consistently high in their blood glucose and insulin levels. These individuals may need to be kept off grass permanently and managed purely on a high fibre diet. Remember, the major threat to our horses and ponies suffering from EMS is laminitis. As long as recovery from the laminitis is achieved, then with correct diet and exercise the prognosis for EMS is good.

Source: http://www.whvc.co.uk/wpnew/wp-downloads/ems.pdf