Caused by the development of either a growth in the pituitary gland (pituitary adenoma) or enlargement of the gland (hyperplasia). The pituitary is a small, hormone producing, gland found at the base of the brain.

(Pars intermedia generally affected in horses rather than pars distalis in other species. Pars distalis is major source of ACTH(adrenocorticotrophic hormone), on which corticosteroids have a negative feed back effect. Pars intermedia in normal horses produces some ACTH but does not have a negative feed back.)Hyperadrencorticism


Diagnosis: Often just from the clinical signs – Laminitis in old, hairy animals.

There are a variety of blood tests that can be done, the more diagnostic ones being more complicated to do.


In my opinion, laminitis occurs due to the effect of cortisol on glucose metabolism in the feet, as in Equine Metabolic Syndrome. I believe that these two conditions are best managed by providing a suitable diet for the age and condition of the horse, generally low in NSCs (See Fructans and Management of laminitis), and where possible to maintaining the horse in some form of exercise. This may not be possible due to the horse’s age or coping with chronic laminitis or for other reasons.

It may be beneficial to clip the horses.

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