As one ages there is gradual degeneration of parts of the body. In some ponies and horses this involves the hypothalamus, a gland at the base of the brain which secretes a neurotransmitter called dopamine. The reduction in dopamine levels permits a neighbouring gland, the pituitary, to produce excessive amounts of hormones ACTH and cortisol which conspire to effect various changes: abnormal coat (long, curly), abnormal fat distribution (bulging above the eyes), pot belly, loss of muscle tone, sweating, increased appetite, thirst and urine production, lethargy, repeated bouts of laminitis and recurrent infections.
Diagnosis: clinical appraisal provides valuable information and confirmation may be obtained from blood sampling to measure ACTH levels or using the dexamethasone suppression test’.
Management: as for Equine Metabolic Syndrome, but medication would be aimed at pituitary suppression using pergolide at an appropriate dose.