Ataxia and paralysis associated with bovine ephemeral fever infection.

Three adult cattle that had been ataxic for 5 to 7 months and a bull that had been paralysed for 24 days following bovine ephemeral fever infection were studied clinically and pathologically. Severe bilaterally symmetrical Wallerian degeneration was demonstrated in the spinal cords of all 4 cattle; in 3 animals an area of primary damage was present in the first cervical segment of the cord and in the other animal it was at the level of the lumbar cord. Pressure on the cord resulting from trauma was considered to be the most likely aetiology because of the similarity of the lesion to other syndromes causing pressure on the cord and the absence of the usual inflammatory changes seen with infectious agents.