After decades of extensive studies and research conducted worldwide by top universities, leading equine nutrition experts, veterinarians, and research centers, we have discovered so much about metabolic conditions and the effects they can have on our horses and ponies. While terminology such as Equine Polysaccharide Storage Myopathy and Pituitary Pars Intermedia Dysfunction can sound overwhelming, many of the common metabolic conditions can be broken down into basic understanding. Join us as the equine experts at The Mill deliver a broad understanding of some of the most common metabolic conditions with tips on prevention and management, with an emphasis on nutritional guidelines.
EPSM (Equine Polysaccharide Storage Myopathy) – Genetic Disorder
Condition resulting from a genetic mutation that causes an inability to utilize glycogen in the muscle
Common Presentations:
- Reluctance to Move
- Sweating
- Poor Performance
- Undiagnosed Lameness
- Muscle Soreness Tremors
Management
- Regular Exercise
- Diet:
- Moderate to Severe Cases - Whole diets, including forage, that consist of 12% or lower NSC levels (AKA: Low Levels of Sugars and Starches)
- Minor Cases and Prevention – Whole diets, including forage, that consist of 20% or lower NSC levels. (AKA: Controlled Levels of Sugars and Starches)
- Antioxidant Support with Vitamin E & Selenium
- Strictly Managed High Fat; High Fiber Diet with close attention paid to sugar and starch levels
- Regular Farrier and Dental Work
- Veterinarian Direction for Medical Treatment, Medications and Support
PSSM (Polysaccharide Storage Myopathy) – Muscle Disorder
Condition resulting from a genetic disorder that causes muscle cramping, pain, stiffness and tying up from abnormal sugar build-up in the muscles. Diagnoses have been categorized into two separate types, PSSM1 & PSSM2.
- PSSM1 – Muscle disorder caused by genetic mutation commonly affecting Quarter Horses and other breeds with QH influence, as well as Draft and Warmblood breeds.
- PSSM2 – Muscle disorder mimicking PSSM1 but without the same gene mutation as PSSM1. True cause is unknown and is most commonly found in Warmblood breeds.
Common Presentations
- Reluctance to Move
- Sweating
- Poor Performance
- Undiagnosed Lameness
- Muscle Soreness
- Tremors
- Muscle Tone Deterioration
- Tying Up
Management
- Regular Exercise – Daily turnout AND a consistent, intentional daily exercise program – even if it’s a low impact routine
- Diet:
- Whole diets, including forage, consisting of 12% or lower NSC levels (AKA: Low Levels of Sugars and Starches)
- Oil Supplement rich in Omega 3 Fatty Acids
- Antioxidant Support with Vitamin E & Selenium
- Strictly Managed High Fat; High Fiber Diet with close attention paid to sugar and starch levels
Tying Up (Exertional Rhabdomyolysis) – Painful Muscle Cramping
Condition resulting from over exertion, anxiety and/or electrolyte imbalances; most common in fillies and mares.
Common Presentations
- Painful, Tight Muscles, especially over the back and hindquarters
- Muscle Tremors
- Reluctance or Inability to Move
- Sweating
- Rapid Heartrate
- Quick shallow breathing
Management
- Work closely with a veterinarian to determine cause and course of action, including rest and exercise
- Diet:
- Whole diets, including forage, consisting of 12% or lower NSC levels (AKA: Low Levels of Sugars and Starches)
- Oil Supplement rich in Omega 3 Fatty Acids
- Antioxidant Support with Vitamin E & Selenium
- Encourage water consumption
- Call on an equine nutritionist to work in tandem with the veterinarian to identify and balance any nutritional deficiencies and imbalances
IR (Insulin Resistance) – Insulin Dysregulation
Metabolic condition that results from being overweight or overwhelming the digestive system with specific carbohydrates. This condition is often compared to Equine Metabolic Syndrome but stems solely from diet; indicating that proper management and prevention is key.
Common Presentations
- Obesity
- Gains weight easily, quickly or for no reason
- Failure to lose weight
- Cresty Neck
- Abnormal Fatty Deposits
- Laminitis with Founder
- While being overweight is the predominate risk factor leading to Insulin Resistance, seemingly ideal weight horses and ponies without previous incidence can develop IR if their digestive tract is overwhelmed with sugars and starches.
Management
- Regular Exercise – Daily turnout AND a consistent, intentional daily exercise program – even if it’s a low impact routine
- Diet:
- Whole diets, including forage, consisting of 10% or lower NSC levels (AKA: Low Levels of Sugars and Starches)
- Strictly Managed High Fat; High Fiber Diet with close attention paid to sugar and starch levels
- Regular Farrier Work
- Veterinarian Direction for Medical Treatment, Medications and Support
EMS (Equine Metabolic Syndrome) – Insulin Dysregulation
Laminitis prone, hormonal, condition resulting from the inability to properly metabolize sugar.
- Disorder most commonly found in Arabians, Donkeys, Quarter Horses, Morgans, Mustangs, Paso Finos, Ponies, Saddlebreds, Tennessee Walking Horses and Warmblood breeds
- Very high risk of developing laminitis with founder
- Similar symptoms to other metabolic disorders but different origin
Common Presentations
- Obesity
- Gains weight easily, quickly or for no reason
- Failure to lose weight
- Cresty Neck
- Abnormal Fatty Deposits
- Irregular growth rings in hooves Laminitis with Founder
Management
- Regular Exercise – Daily turnout AND a consistent, intentional daily exercise program – even if it’s a low impact routine
- Diet
- Whole diets, including forage, that consist of 10% or lower NSC levels (AKA: Low Levels of Sugars and Starches)
- Strictly Managed High Fat; High Fiber Diet with close attention paid to sugar and starch levels
- Regular Farrier Work
- Veterinarian Direction for Medical Treatment, Medications and Support
PPID (Pituitary Pars Intermedia Dysfunction) AKA Cushing's Disease - Endocrine Disorder
Condition that affects the endocrine system resulting from a benign tumor growing on the pituitary gland. Tumors like these usually typically arise in aged horses and ponies and cause an increase in hormone release.
Common Presentations
- Weight Loss
- Poor Coat Quality – Long, Shaggy Hair - Inability to Shed-Out Properly
- Unwarranted Sweating -OR- Failure to Sweat
- Decrease in Energy/Lethargy
- Prone to Laminitis
- Excessive Thirst and Urination
- Cresty Neck and/or Abnormal Fat Deposits
- Decreased Immune Function
Management
- Regular Exercise
- Whole diets, including forage, that consist of 15% or lower NSC levels (AKA: Low Levels of Sugars and Starches)
- Body Clipping
- Parasite Control
- Regular Vet, Farrier and Dental Work
- Weakened Immune System
Additional Tips – Caring for horses and ponies with or prone to metabolic conditions requires rigorous management.
*** The number one goal for all horses and ponies dealing with metabolic conditions is limiting the amount of sugars and starches consumed in their total daily diet, this includes their forage. ***
There is not a ‘one-size-fits-all’ solution or secret management formula that addresses the needs of every metabolic horse. However, being under the direct supervision and guidance of a veterinarian and implementing any one or combination of these other practices can help to successfully manage and prevent metabolic issues.
Diet Balancers
Diet balancers are a great way to fulfill the daily requirements of vitamins, minerals and amino acids for horses and ponies without the added calories, sugars and starches. Great option for horses that are…
- Overweight
- Easy keepers
- Dealing with metabolic conditions
- Needing additional protein support
- High performance
- Pregnant
- Lactating
- Improving Body Condition
- Advanced Age
True diet balancers have a low feeding rate; typically, 1/2lb to 3lbs per day depending on size and work level. They can be fed as a top dress with their feed and forage or alone with their forage. Because a horse’s digestive system can only absorb so many nutrients at once, it is advised to break down their daily ration into at least 2 meals per day.
Hay & Hay Alternatives
Forage is the foundation of the diet for all horses and ponies. When dealing with metabolic conditions, choosing the right forage can be detrimental to their overall health and wellbeing. Choosing the wrong option can further exacerbate metabolic symptoms causing additional medical problems, up to and including death. Some things to keep in mind…
- Grass hays such as timothy and orchard grass tend to have higher levels of sugar than legumes such as alfalfa
- While legumes typically have lower sugar levels, they tend to be more calorically dense than grass hays
- On average, hay that is less mature contains higher levels of sugars than more mature hay
- Hay alternatives such as chopped forage, hay cubes, hay pellets and beet pulp can be helpful in managing metabolic horses and ponies by providing the forage base their system needs while controlling the levels of sugar they consume. Some chopped forage options have guaranteed low NSC levels. If considering beet pulp, opt for the molasses-free options.
Soaking Hay
Soaking hay is not a cure-all management practice and does not ensure safe forage for every horse. However, it is a widely used practice to help reduce the level of sugars in hay prior to feeding it. 30 minutes in cold water is sufficient to reduce some of the sugars without striping other valuable nutrients. Be sure to give the soaked hay plenty of time to drain and discard the soaking water before offering it to the horse.
Multiple Feedings
Breaking daily feed, supplement and forage regiments into small, frequent meals throughout the day and night can be a useful management practice.
- Mimics natural grazing behavior
- Keeps gut happy with steady gut fill
- Prevents gorging from hunger and overwhelming the digestive tract
- Allows better digestion of nutrients
Grazing Management
Limiting the amount of free time in the pasture for grazing is only one part of the battle when dealing with metabolic horses and ponies. Managing WHEN to offer grazing is equally as critical. The sugar level in grass increases when exposed to sunlight. Consequently, intentional turnout between 3am and 10am are best suited for individuals with sugar sensitivities. Additionally, it is important to remember that when grass is ‘stressed’ it fights for survival. It does so by spiking its sugar levels in attempt to overcome the life-threatening situation. Stress response in grass is brought on by any condition that jeopardizes its ability to thrive, such as extreme temperatures, drought, floods, mowed down too short or over-grazed to name a common few.
Muzzles, Slow Feed Hay Nets & Dry Lots
Muzzles, slow feed hay nets and dry-lots are extremely helpful tools used to help regulate forage intake; thereby reducing the amount of consumed sugar and starch.
- Muzzles can reduce forage consumption by up to 30% and allow the horse to participate in their normal roaming and grazing behaviors. While muzzle wearing, alone, may not be enough to fully control their sugar and starch intake, it is a wonderful tool that most horsemen have in their barns.
- Slow Feed Hay Nets are great options when horses are in confined spaces like stalls and dry lots. They allow the horse to still eat continuously, if they like, yet can significantly reduce the rate of consumption. This is helpful to satisfy their gut-fill needs without overindulging. Dry lots significantly increase the control of sugar and starch consumption and are ideal for extreme cases. It is important that the dry lot be truly dry. Weeds and stressed grass contain just as much sugar as grass, in many cases more.
- Dry-lots allow the horse to be outdoors in a space to move about freely without the danger of ingesting too much sugar. If using a dry lot be sure to provide adequate forage by way of hay or hay alternatives and never allow the horse to go longer than 3-4 hours without gut-fill.
