Bird flu has been confirmed at a second premises near Penrith.
The Animal and Plant Health Agency said it had been found a large commercial poultry enterprise.
All poultry will be humanely culled.
A 3km protection zone and 10km surveillance zone has been declared around the premises.
Last month, bird flu was confirmed in Wetheral, near Carlisle. Control zones remain in place there.
The 3km protection zone requires all captive birds to be housed to prevent them from coming into contact with wild birds, which can spread the virus.
The 10km protection zone means people must get a licence to move birds or mammals, except for pets, and they cannot move poultry litter, manure, or slurry.
People must also keep records of poultry and eggs that move in or out of their premises, with an exception for table eggs going directly to consumers.
