Muscle hypertonicity in the cavalier King Charles spaniel--myopathic features
Wright, J.A.; Brownlie, S.E.; Smyth, J.B.; Jones, D.G.; Wotton, P.
Veterinary Record 118(18): 511-512
1986
ISSN/ISBN: 0042-4900 PMID: 3716135 Document Number: 277256
Detailed examination of eight cases of muscle hypertonicity revealed previously unrecorded abnormalities. In three dogs there was no spontaneous activity in any limb or spinal muscle, although motor nerve conduction velocity was normal in the tibial or ulnar nerves. Muscle biopsy showed small vacuoles between myofibrils in some fibres stained with toluidine blue. Electron microscopy showed dilatation and proliferation of the sarcotubuler system and hydropic degeneration of mitochondria. Exaggerated muscle tone was a definite feature not recorded by other workers. Seven of the eight dogs were males and five had a single male ancestor which had been mated to the same female in three out of five cases. The possibility of the condition being inherited is noted.