Leporine dysautonomia: further evidence that hares suffer from grass sickness.

The recently described dysautonomia of hares has many similarities to equine grass sickness, particularly when the autonomic ganglia of affected hares and horses are compared by light microscopy. This study shows that the ultrastructural findings are also similar, with a loss of ribosomes from the rough endoplasmic reticulum and distension of its cisternae; the Golgi apparatus is not recognisable in affected neurons. Membranous stacks were identified in autonomic neurons of affected hares, a feature not characteristic of equine grass sickness but often found in feline dysautonomia. Staining with wheat germ agglutinin, a lectin recognising Golgi membranes, showed a lack of reactivity in affected neurons again suggesting a lack of a normal Golgi apparatus.