I also would like to know because I have an old mare who was diagnosed borderline Cushings in the fall.

Another question: if a horse is IR and is being well maintained by diet and showing nome of the signs of being IR currently, will testing diagnose the underlying IR condition? I ask because I put a mare of mine on an IR diet without testing her (vet at the time was not helpful about her fatty teats and fat deposits, I changed vets later), she is doing well, but if I need to have the old mare tested, I might start a file on this mare also. I had posted my hay results for the old mare but couldn't figure out how to balance it and then had to put the old mare on different hay for her health issues and got sidetracked by that issue.

Donna