Thromboembolic meningoencephalitis diagnosed in Natal.

Nine feedlot cattle showed clinical signs consistent with those expected in thromboembolic meningoencephalitis. These signs included pyrexia, ataxia, posterior paresis, paralysis and coma. Brown necrotic foci with haemorrhagic borders were observed in the brains of three animals that had died. In these foci vasculitis, thrombosis, infarction and neutrophil infiltration were observed during microscopical examination. Haemophilus somnus was isolated in pure culture from the brains.