A spongiform degeneration of the white matter in 2 out of 8 Australian cattle dog littermates is described histologically. On the neurological examination, these dogs showed sternal decubitus, inability to walk and loss of coordination. A cerebellar ataxia was suspected. Microscopically, marked vacuolation of the white matter was observed in the cerebrum, cerebellum and dorsal funiculus of the spinal cord. A severe hypertrophy of astrocytes with pale and swollen nuclei and eosinophilic cytoplasm was also observed. This pathology has been described in several animals species but this is the first description in the Australian cattle dog.