More than 30,000 animals are reportedly susceptible in the current outbreak, with 52 cases resulting in 52 deaths, and 20,400 birds destroyed.
Restriction zones have been established and the affected premises have been disinfected.
Meanwhile, restrictions on a Scotland farm that was hit by ND have been lifted.
Around 14,000 birds were culled after the discovery of the disease in a flock of grey partridges in East Lothian last month.
Health officials from the Scottish Executive
said there had been no further outbreaks of the virus and restrictions were being lifted in line with EU rules.
But the source of the outbreak remains a mystery and officials warned farmers to be vigilant should further cases emerge.