Polysaccharide Storage Myopathy

Exertional rhabdomyolysis (ER) occurs in about 3% of exercising horses affecting a wide variety of breeds (Cole et aI, 2004). Terms such as tying-up, set fast, azoturia and Monday Morning disease have been used to describe this syndrome. During acute episodes horses exhibit clinical features of muscle stiffness, cramping, sweating and reluctance to move forward. For many decades it was assumed that there was one cause for this condition
because clinical signs were very similar amongst acutely affected horses.
However, once the muscle biopsy technique was introduced to equine medicine it became clear that there are distinct causes for ER which differ in molecular or environmental bases, recurrence, prognosis and responses to management changes (Valberg S.l, 2002) ...