A 10-month-old American cocker spaniel was evaluated for megaesophagus
, aspiration pneumonia, but no appendicular muscle weakness. During ho
spitalization, weakness of the facial muscles developed, this resolved
with anticholinesterase administration. Serum antibodies against acet
ylcholine receptors were documented, confirming the diagnosis of focal
myasthenia gravis. Diagnosis, mangement, and medical treatment are di
scussed.