Changes

===Clinical Signs===

===Clinical Signs===

Because of their high natural resistance to tetanospasmin (compared to the horse and man), affected dogs may have a longer incubation period and clinical signs may be mild; a change in gait may be the only reported historical abnormality. The localised form of tetanus that develops in the dog may be difficult to diagnose, particularly if no wound is apparent. Unlike the generalised spastic paralysis described in horses, dogs may present with a wound to a single limb (often a thoracic limb) and unyielding stiffness or rigidity in the surrounding area. The rigidity may spread to the contralateral limb and then begin to advance cranially, becoming generalised as the disease progresses. As reported in horses, dogs may display hypersensitivity to even minimal amounts of stimulation. Affected animals have also been reported to display caudal displacement of the ears, lateral canthi and commissures of the eyes. Prolapse of the nictating membranes, trismus (excess jaw tone) and retracted lips (risus sardonicus) are other noted clinical features.  

Because of their high natural resistance to tetanospasmin (compared to the horse and man), affected dogs may have a longer incubation period and clinical signs may be mild; a change in gait may be the only reported historical abnormality. The localised form of tetanus that develops in the dog may be difficult to diagnose, particularly if no wound is apparent. Unlike the generalised spastic paralysis described in horses, dogs may present with a wound to a single limb (often a thoracic limb) and unyielding stiffness or rigidity in the surrounding area. The rigidity may spread to the contralateral limb and then begin to advance cranially, becoming generalised as the disease progresses. As reported in horses, dogs may display hypersensitivity to even minimal amounts of stimulation. Affected animals have also been reported to display caudal displacement of the ears, lateral canthi and commissures of the eyes. Prolapse of the nictating membranes, trismus (excess jaw tone) and retracted lips (risus sardonicus) are other clinical features.