This is a sex-linked inherited muscle disease.

  Affected puppies appear normal at birth but they start showing symptoms between 7 and 19 weeks of age.

Symptoms include progressive skeletal muscle atrophy, muscle weakness especially in the hind limbs, small stature compared to unaffected littermates, puppies can walk with short choppy strides, collapsing after few strides, difficulty eating due to weakness in mastication muscles, which may lead to dropped jaws, hoarse bark.

The disease progresses rapidly and puppies become unable to stand or raise their heads by 3-4 weeks after the start of the symptoms.

Unfortunately affected dogs are usually euthanized between 15-26 weeks of age.

Due to the X Linked recessive mode of inheritance, females are rarely affected affected and the disease is primarily found in males.

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