Page 964 - The Veterinary Care of the Horse

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VetBooks.ir ENDOCRINE DISORDERS

PITUITARY PARS INTERMEDIA DYSFUNCTION (PPID) –

EQUINE CUSHING’S DISEASE (ECD)

Equine Cushings Disease is now known as pituitary pars intermedia dysfunction (PPID). It is
a syndrome caused either by enlargement (hyperplasia) or a benign tumour (adenoma) of the

pars intermedia of the anterior lobe of the pituitary gland which is situated at the base of the
brain (Figure 20.1). These cause increased production of adrenocorticotrophic hormone

(ACTH) which is released into the bloodstream and stimulates the adrenal glands to produce
cortisol. The condition develops slowly and the symptoms which develop due to the raised

cortisol levels and pressure on adjacent parts of the brain are slowly progressive.