The following is something I copied from an article written on
cushing's. I hope to have the whole article copied by the end of the
week to put in our files.

The average age of Cushing's horses is 19 years. Mares, geldings,
stallions of all breeds appear to be equally afflicted. Ponies appear
to develop the disease more often than do horses.
Many horses with the disease exhibit the classic thick, long curly
coat that may not shed. Less striking coat changes are also seen,
including a slightly heavier than usual winter hair coat. Shedding
later in the spring, patchy slow shedding and regrowing winter coats
earlier in the fall than ohter animals housed under similar
conditions. Obvious abnormalities may not be apparent early in the
course of the disease, however, change in shedding behavior and/or the
apperance of "guard hairs" along the chin or neck in the summer may be
an early indication of equine cushing's disease.
Other clinical signs of Cushing's disease include and increased
tendency to founder, excessive water drinking and urinating, excessive
sweating, muscle wasting, poor wound healing and elevated respiratory
rates. Mares may fail to cycle normally or fail to conceive when bred.

Hope this helps the people newer to this group.
Mary G. & Marvin