HOLTON, England -- Britain scrambled to contain its first outbreak of the highly pathogenic H5N1 strain of bird flu in domestic poultry yesterday after the virus was found at a farm run by Europe's biggest turkey producer. About 2,500 turkeys have died since Thursday at the Bernard Matthews farm near Lowestoft in eastern England. The Department for the Environment, Food and Rural Affairs (DEFRA) said all 159,000 turkeys on the farm would be culled. "We're in new territory," National Farmers' Union Poultry Board Chairman Charles Bourns said. "We've every confidence in DEFRA, but until we know how this disease arrived,...