Final answer:
Equine Polysaccharide Storage Myopathy (EPSM) in horses is related to glycogen storage diseases and involves the abnormal buildup of glycogen in muscle tissues, leading to stiffness, pain, and possible muscle damage.
Step-by-step explanation:
Equine Polysaccharide Storage Myopathy (EPSM or PSSM) is a genetic muscle disease found in horses that presents with a variety of symptoms. The condition is akin to glycogen storage diseases in humans, where there is a build-up of abnormal forms of glycogen in the body's tissues, leading to progressive muscle weakness. In horses with EPSM, the storage and metabolism of glycogen within the skeletal muscles are abnormal.
Some common symptoms of EPSM include muscle stiffness, weakness, and pain, which can lead to reluctance to move, sweating, and trembling. In severe cases, horses may exhibit signs of colic due to muscle damage. The disease most often affects the skeletal muscles but can also have consequences for other organ systems. Monitoring and managing glycogen intake through diet is crucial for horses with this condition, to prevent the exacerbation of symptoms.