I think some of this relates to the movement of livestock that may still be contaminated by radiation from the 1986 Chernobyl disaster and also part of controls to prevent the spread of foot and mouth.
Tags are in the front line of prevention in that they allow the tracking of livestock anywhere in the country, care must also be taken with welsh sheep and goats, particularly in areas around Hereford where live stock are known to carry high concentrations of human proteins.
