PPID (equine Cushings disease) is the most common endocrine disorder in older horses — advances in diagnosis and treatment are substantially improving affected horse welfare.
PPID welfare management has improved markedly with the recognition of seasonal ACTH variation and the development of better diagnostic reference ranges. Many horses previously considered "just aging" had undiagnosed PPID with associated chronic discomfort from laminitis, muscle loss, and impaired immune function. Diagnosis using appropriate seasonal reference ranges enables treatment initiation significantly earlier in disease progression. Pergolide treatment improves quality of life for most affected horses: coat shedding returns, muscle condition improves, laminitis risk reduces, and energy levels increase. Annual ACTH testing for horses over 15 years, with retesting during the seasonal peak (September-October in Northern Hemisphere), is the welfare-optimal approach to identifying and treating this highly prevalent condition.