The infection of poultry with H5 influenza A virus was confirmed on 13 April, by Dr Toshiro Kawashima of the Animal Health Division of the Ministry of Agriculture, Forestry and Fisheries in Tokyo.
Two hundred broilers had already died from the disease, at a farm in Kuma-gun, Taragi-machi, with the remaining 56,200 susceptible birds now destroyed.
Restrictions on movement have been imposed on farms within a three-kilometre radius of the infected area, while shipment restrictions are imposed within a three- to 10-kilometre radius of the affected farm.
It is the first outbreak of the listed disease since March 2011, according to the World Organisation for Animal Health (OiE).
The report, published by the OiE yesterday, said the source of the origin of the infection was unknown.
Hong Kong has banned the import of poultry and poultry products from the region, according to the Centre for Food Safety at the Food and Environmental Hygiene Department.