The presence of PrPres is regarded as a marker for the disease. Five further rapid tests are currently under examination. All three tests operate by detecting the infectious agent or marker PrPres in the central nervous system. Following slaughter of the animal a sample of brain or spinal cord is taken from the animal using a special tool. This tissue is taken to the laboratory and tested for the presence of PrPres.
Rapid tests are quick and reliable, and allow large numbers of samples to be tested.
Tests may be used for surveillance and also to provide additional protection for the consumer. Surveillance Tests can be used to determine if BSE exists in a population and to obtain an indication of its prevalence. Used over time these can be used to monitor changes in the level of the disease. This type of surveillance can be carried out by testing risk groups of animals, especially cows which have died on farms or cows presented for emergency slaughter. If BSE occurs, it is more likely to be found in this population so the sampling is more effective.