Ask the Nutritionist: Dr. Getty's Forum for Equine Nutrition
Welcome to my forum.
Here you will find more than 6 years of questions and my answers. It is searchable and offers a great deal of information.
Currently, I am discontinuing new questions. This may change in the future, but in the meantime, please know that It has been a true pleasure serving you.
Take a look at my Nutrition Library and Tips of the Month for a variety of answers on selected topics. Be sure to sign up for my monthly e-newsletter, Forage for Thought.
I also have a growing number of recordings on "Teleseminars on Nutrition Topics that Concern You" as well as the new, Spotlight on Equine Nutrition Series -- printed versions of favorite teleseminars.
And finally, look for my articles in a variety of local publications and online newsletters, as well as the Horse Journal, where I am the Contributing Nutrition Editor.
All the best,
Dr. Getty
Greetings Debbie,
Grass hay, regardless of the type, can vary tremendously in its sugar and starch content. And you really cannot tell by looking at it if it is safe for a cushingoid horse. The best approach is to have it tested. You can call your county extension service or mail a sample to Equi-Analytical Labs -- www.equi-analytical.com Order their Equi-Tech test which is $26 and will give you the percent WSC (water soluble carbohydrates), and the percent starch. Add these two numbers together to get percent NSC (non-structural carbohydrates). %NSC should be less than 12% to be safe.
Coastal Bermuda can be safe for horses if you find one that is cut more finely and is not overly mature. Mature hay has more fibrous stems and if the cut is long, the combination of indigestible fiber and lengthy stems may lead to impactions. I had my horses on Coastal Bermuda for years when I lived in Texas and always looked for a immature cut -- softer leaves. But, here too, you'll need to have it tested since every hay batch differs.
There may be some natural prairie grasses available in your area. This may be another option.
Keep me posted.
All the best,
Dr. Getty 
Author of Feed Your Horse Like A Horse
Where are you from? Bayfield, CO