The livestock should have been logged into the Department for Environment, Food and Rural Affairs' tracking system but something went wrong, The Daily Telegraph reported Monday.

"Laptops, data and now cows, is there anything this government cannot misplace?" asked Peter Ainsworth, the Shadow Environment secretary. "Defra's performance would do credit to Little Bo Peep."

The cattle tracing system was set up to protect the public and animals after the mad cow and foot and mouth epidemics.

Last week Britain's Ministry of Defense revealed a computer hard drive with the private details of 100,000 members of the Armed Forces was missing.

In August, a memory stick containing data on all prisoners in England and Wales was lost by a Home Office contractor.