Over 100,000 chickens on a poultry farm in Friesland have been culled because of bird flu, taking the total number of birds killed since the outbreak began last year to some 3.5 million.

The birds, which were being raised for meat, were on a farm in Minnertsga. The owner has two other broiler farms within three kilometres of the affected location and they will be monitored closely for two weeks to see if the virus has spread, the farm ministry said.

Ten other poultry firms located at less than 10 kilometres from the epicentre of the most recent outbreak have been banned from moving birds, eggs, straw and manure for the coming period.

The Dutch poultry sector is currently grappling with its most severe bird flu outbreak for 20 years and all poultry, including organic chickens, have been kept indoors since October in an effort to stop the spread.

The Netherlands has some 1,700 poultry farms, half of which produce eggs – totalling some 10 billion eggs a year. Bird flu infections have so far been found on 50 farms, most of which were producing eggs.