Dr. Brian Eitelman, DVM, CJF and Aggie Vet and Farrier Services provide veterinarian and farrier services in Parker, CO, Elizabeth, CO, Franktown, CO, Castle Rock, CO, Sedalia, CO and Larkspur, CO. To learn more, please visit us at www.vetandfarrier.com
In this series, Dr. Brian discusses the main metabolic diseases in horses.
In part 2, we go over care and management of metabolic horses, testing, medications, how to understand and adjust carbohydrate content in their diets, soaking hay, how much hay to feed your horse, and exercise strategies.
Managing equine metabolic syndrome or EMS and pituitary pars intermedia dysfunction or PPID in horses:
I can’t stress enough how important exercise and a correct and intentional diet is for metabolic horses. Please talk with your vet about the needs for your individual horse. The proper diet is critical - please don’t skip by this just because it can be challenging. Great news: A well-managed diet is one of the BIGGEST ways we can improve these conditions in your horse. Bad news: lack of dietary management almost certainly negates everything else we can do and all but guarantees laminitis and founder. We can only do so much with medications.
Testing
Moving on to testing. Metabolic testing is an evolving science. There are a lot of testing options and they can be tough to navigate. There usually isn’t a one size fits all magic test. Testing mostly revolves around good basic blood work - looking at organ function, inflammation, and overall health - as well as various ways of measuring ACTH, Insulin, Cortisol, and Thyroid.
So why test? Why not just wing it based on common presentation? I myself used to say, “If you can’t diagnose the horse from across the street, it’s probably not too bad.” But don’t forget how I started Part 1, MULTIPLE DISEASES CAN BE PRESENT. Minimal testing gives a minimal picture and in most cases, it is worth knowing more of what is going on. A better baseline allows for not only a better and more complete diagnosis, but better and more accurate adjustments of medications, diet and exercise. Metabolic diseases are usually “permanent” conditions. Please don’t skimp on testing, especially in the early stages. Know your enemy and you have a much better chance of winning.
Medications
This part is going to be brief mostly because this is such an evolving field. Please talk with your vet about your horse’s individual needs and again - testing is a large part of giving you the best answer!
For EMS, good news: there isn’t a great medication at this time for this disease. Bad news: there isn’t a great medication at this time for this disease. The cornerstones for managing this disease: you guessed it - diet and exercise!! There are some meds out there that we can use to give the horse’s systems a bump - thyroid supplements and some newer drugs trying to improve sensitivity to insulin. There are a few horses that truly have low thyroid, but most often, the thyroid supplement is used as a temporary boost to metabolism.
For PPID, the drug of choice at this time is Pergolide or Prascend. This replaces the brakes in the system we talked about in Part 1. Again though, we can only do so much with meds. Diet and exercise are still key for these horses as they are also very prone to laminitis and founder.
Diet
The main focus point for managing a diet with metabolic horses is carbohydrates or for ease of understanding - “sugars.”
There are a couple of ways to break down the carbohydrates found in forage.
The first is digestible or undigestible. As plants mature, some of the digestible carbohydrate content shifts to undigestible as the plant has to reinforce its stalk or stem to support its weight and height. If you were looking for the most nutritious hay possible, you would look for “leafy” hay and stay away from the stuff that’s “all stems.” That’s why - the more prominent the stems, the less nutritional content is available for digestion.
Another way to count the carbs is nutrition analysis and that will contain two important numbers - NSC (non-structural carbohydrates) and WSC (water-soluble carbohydrates). A simple way to think about these two - NSCs are all of the potentially digestable/absorbable carbs and WSC are the sugars and most-importantly - the carbs we can take out of how with proper soaking.
Extended soaking (12+ hours) is a great way to limit the liability of all the nutritious hay we have around. Unfortunately, one of the biggest challenges we face is the cold winters. If soaking hay becomes impossible or unlikely regardless of the time of year - consider seeking out less nutritious, poorer quality forages. Something like mature native grasses that have been stored well. These aren’t the easiest to find so an ideal balance may be something like soaking hay for the 9-10 months it is feasible and having a small stockpile of poor hay for those times when it is too cold for soaking.