The disease was first diagnosed in 1986 in Great Britain. BSE has had a substantial impact on the British livestock industry. The disease also has been confirmed in domestic cattle in Ireland, France, Portugal, and Switzerland and in cattle exported from England to Oman, the Falkland Islands, Germany, Denmark, Canada, and Italy. Clinical Signs Cattle affected by BSE experience a progressive degeneration of the nervous system.
Affected cattle die.
The causative agent of the disease is not completely characterized, and there is no treatment. Following the onset of clinical signs, the animal's condition deteriorates until it either dies or is destroyed. This usually takes from 2 weeks to 6 months. Most cases in England have occurred in dairy cows between 3 and 5 years of age. BSE is so named because of the spongy appearance of the brain tissue of infected cattle when sections are examined under a microscope.