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     EQUINE METABOLIC SYNDROME (EMS) is one of the most common diseases we see in practice.  When horses get too fat, they develop metabolic changes similar to those that overweight humans get with TYPE 2 DIABETES.  Obesity may lead to what we call "inappropriate fat deposits."  In horses, these develop in the crest of the neck, behind the shoulders and beside the tail head.  In both horses and humans it used to be believed that fat was simply a storage organ, however we now understand that the cells found in inappropriate fat storage areas produce hormones interfering with how the body uses insulin, causing INSULIN DYSREGULATION.  This in turn affects the way the body handles glucose (sugar) at a cellular level.  Affected horses also get elevated insulin and  CORTISOL, a hormone from the adrenal gland.

     The most serious side effect from INSULIN DYSREGULATION in horses is LAMINITIS.  You might know of situations where horses have overeaten on lush grass or eaten too much grain and developed laminitis.  The metabolic changes in such cases are pretty similar to what we see in EMS.  In fact obese horses with EMS can often very easily develop laminitis with even small amounts of extra sugar from feeds.  There are numerous causes of laminitis, but regardless of the exact cause, horses with EMS will be very much more susceptible.  

     So why does this occur?  Animals all have different metabolisms, but simply put, if a horse is obese, it is eating more food than it is burning up. Energy requirements vary with breed, genetics, age, body type and work level.  We certainly see it following family lines.  Another factor is that often our pastures or hays contain too much energy for the easy life most horses live.  Wild horses that typically eat low quality feeds and have been observed to move up to 50 km each day as they graze and move about for food and water.  

   Obviously prevention is the key, but what can be done once your horse is obese and has EMS ?  WEIGHT LOSS  is the solution.  This can only be accomplished by decreasing  calories and increasing exercise (sound familiar?)  Feed intake will need to be strictly controlled and hopefully the horse has not yet developed laminitis so it can be exercised to burn up fat.  ONLY WHEN THE HORSE HAS BURNED UP THE INAPPROPRIATE FAT DEPOSITS WILL THE EMS STATE BE CORRECTED.    

     As we know, dieting is not easy.   First you need to find some LOW SUGAR HAY.  Many good hay producers now test their hay.  You will need to weigh your feed at first and soaking your hay in water for a few hours then pouring off the water will further reduce the sugar content by as much as 30%. You will need to ruthlessly REDUCE THE AMOUNT OF FEED!   Feed ABSOLUTELY NO TREATS!!!!!

     EXERCISE your horse as much as possible.  The best way to monitor progress is to measure the girth of the neck with a tape measure.  In severe cases, including those that already have sore feet, we may put them on medication to rev up their metabolism so that they burn up more calories.  We like to examine these horses and discuss a plan with you.                

Edited Image 2016-02-06 01-06-34
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