HL Deb 19 January 1998 vol 584 c219WA
Lord Vinson

asked Her Majesty's Government:

Whether they are satisfied that the experiments carried out on live cattle to ascertain the transferability of BSE replicated normal farm conditions with sufficient accuracy to ensure that the conclusions drawn are meaningful. [HL27]

Lord Donoughue

The experimental animals were fed 100g of infected brain material. This was recognised at the time that the experiment was started (1991) to be potentially in excess of the natural challenge in most cases. Nevertheless, it was essential to ensure that cattle became infected otherwise the experiment would have produced no meaningful results. We now have evidence that 1g of brain tissue will transmit disease, but only six out of 10 cattle have died as a result so far. It is probable that most cattle became infected by consuming more than the equivalent of 1 g of heat-treated brain, as reflected by their relative incubation periods. A further range of experiments is planned that will examine the consequences of challenge with smaller quantities of brain.