Dutch authorities will slaughter 50,000 birds at a poultry farm after a highly contagious strain of bird flu was discovered nearby, taking to around 300,000 the number of chickens and ducks culled in the Netherlands in recent weeks.

A government statement said tests had confirmed an outbreak of the H5N8 bird flu strain at a farm in the western municipality of Zoeterwoude, where 28,000 laying hens were ordered destroyed on Sunday.

The cull at a nearby farm announced on Monday was a precautionary measure, it said. Animal health authorities are testing poultry at other farms in the area.

Transport restrictions were imposed on the sector two weeks ago that have hit around 2,000 poultry businesses. The Netherlands is the world's largest exporter of eggs and the largest exporter of poultry meat in the European Union.