Pituitary Pars Intermedia Dysfunction (PPID or Cushings disease) is the most common endocrine disorder in horses and is often underdiagnosed, causing preventable suffering in aged equines.
Unmanaged PPID causes significant chronic welfare suffering: the hypertrichosis (long coat) impairs thermoregulation causing heat stress; muscle wasting causes weakness and loss of function; and the associated laminitis causes severe foot pain. Many horses with advanced PPID are managed by owners who attribute signs to normal ageing, delaying diagnosis and prolonging suffering. Blood ACTH testing in late summer (when seasonal PPID ACTH rise occurs) has dramatically improved detection rates. Pergolide treatment, while not curative, effectively controls symptoms in the majority of horses and horses with well-managed PPID can enjoy good quality of life for many years after diagnosis.