Table 1 Additional golden retrievers with degenerative myopathy as of 1988

10 days

M

Body stunting; glossal, shoulder, and neck muscle hypertrophy; bradycardia

NE

NE

Gross body stunting and muscle hypertrophy. Skeletal muscle histologic evidence of variation in fiber size, hyaline fibers with calcification, and basophilia consistent with regeneration; inflammation including giant cells; milder lesions in the heart.

Euthanasia at 10 days

[88]

6–8 weeks (two littermates were described)

M

Stiff gait with progression to a stilted, shuffling gait by 3 months. Fatigue with exercise, occasional respiratory distress, neck stiffness, resistance to jaw opening, and glossal hypertrophy.

Elevated

“Myotonia”

Severe degenerative muscle disease: myofiber necrosis, mononuclear phagocytosis, giant cells, and calcification

Euthanasia at 6–9 months when the dogs were still ambulatory

[91]

4–5 months

M

Generalized muscle atrophy, stiff gait, dysphagia, stenotic breathing, exercise intolerance.

NE

CRDs

Gross muscle atrophy; scattered necrotic fibers undergoing phagocytosis, increased endomysial connective tissue, calcification of myofibers, targetoid fibers, and fiber type grouping; myocardial degeneration and calcification

8 months at biopsy; outcome not given.

[82]

8 weeks

M

Stiff, shuffling gait; simultaneous pelvic limb advancement (bunny hopping); overextension at the carpus, overflexion at the tarsus, and abduction of the paws; stifle adduction; hypertrophy of proximal limb muscles; mild vertebral kyphosis; trismus; drooling.

13,435 IU/l

CRDs and positive sharp waves

4 months: fiber size variation, hyaline and necrotic fibers with myophagocytosis; centrally nucleated fibers; basophilic fibers consistent with regeneration. 8 months: progressive changes with mineralization and endoymysial and perimysial fibrosis; fibers with chains of central nuclei; fiber grouping.

Euthanasia at 8 months

[93]