MYOTONIA IN A COCKER-SPANIEL

A 16-week-old, male cocker spaniel suffering from pelvic-limb ''bunny hopping'' as well as rigidify, spasticity, and ataxia in all limbs was evaluated, The clinical features, electro physiological abnormalities , and muscle histopathological and histochemical evaluations led to a diagnosis of congenital myotonia, Myotonia is a disorder of skeletal m uscle characterized by delayed relaxation of the muscle fiber in respo nse to voluntary, mechanical, or electrical stimulation, The pathophys iology of congenital myotonia remains controversial, currently propose d pathomechanisms are discussed, To the authors' knowledge, this is th e first case of congenital myotonia reported in a cocker spaniel.