Volume 1: Findings and Conclusions
Executive Summary of the Report of the Inquiry
6. Measures to eradicate the disease in cattle

• Once Mr Wilesmith had identified MBM as the probable vector of BSE, the Government introduced the appropriate measure to prevent further infection and to stop the spread of the BSE agent - a ban on incorporating ruminant protein in ruminant feed. This had a dramatic effect in reducing to a fraction what had been an escalating rate of infection. It did not, however, bring infection to an end.
• The manner in which the Government introduced the ruminant feed ban was influenced by misconceptions as to:

- the scale of the infection;
- the amount of infective material needed to transmit the disease.

• Ignorant of the fact that the rate of infection had escalated to thousands of cases a week, the Government gave the animal feed trade a 'period of grace' of some five weeks to clear existing stocks of feed before the ban took effect. Some members of the feed trade, being given an inch, felt free to take a yard and continued to clear stocks after the ban came into force. Farmers in their turn used up the stocks that they had purchased. This led to thousands of animals being infected after the ruminant feed ban came into force on 18 July 1988.
• More serious was a failure to give rigorous consideration to the amount of infective material that was proving capable of transmitting the disease. The false assumption was made that any cross-contamination of cattle feed in feedmills from pig or poultry feed containing ruminant protein would be on too small a scale to matter.
• In fact, as subsequent experiments were to demonstrate, a cow can become infected with BSE as a result of eating an amount of infectious tissue as small as a peppercorn. Cross-contamination in feedmills resulted in the continued infection of thousands of cattle. Because it takes, on average, five years after initial infection for the clinical signs of BSE to become apparent, this was not appreciated until 1994.
• From September 1990 contamination of cattle feed with pig and poultry feed should not have resulted in infection. This was because, following the experimental transmission of BSE to a pig, MAFF on the advice of SEAC introduced a measure in September 1990 aimed at protecting pigs and poultry from BSE. This was a ban on the inclusion in pig and poultry feed of MBM derived from the parts of the cow that might be expected to carry high infectivity if an animal were incubating or suffering from the disease - 'Specified Bovine Offal' or SBO.
• However, there was a failure to give proper thought to the terms of this measure when it was introduced. The animal SBO ban was unenforceable and widely disregarded. Infectious bovine offal continued to find its way into pig and poultry feed and then, by cross-contamination, into cattle feed.
• Only in 1994 did the fact of the continuing infection and the reasons for it become appreciated. Regulations were revised and a rigorous enforcement campaign launched to coincide with the takeover in 1995 by a new national Meat Hygiene Service (MHS) of the enforcement duties in slaughterhouses, previously carried out by local authorities. The success of these measures is now becoming apparent. They were replaced after 20 March 1996 by the radical step of banning the incorporation of all animal protein in animal feed.