WELSH poultry will have to be housed from Friday 2 December, the devolved government has announced.
Free-range poultry farmers must keep birds indoors and review their biosecurity to ensure high hygiene standards and minimal contact with wild birds.
It follows Northern Ireland declaring a housing order to come into force on 28 November.
In England, birds have been housed since 7 November and Scotland is yet to announce any further measures beyond an Avian Influenza Prevention Zone.
Interim chief veterinary officer for Wales, Gavin Watkins, said housing effectively protects birds against avian influenza only if accompanied by rigorous biosecurity to keep the virus out.
“The latest data suggest a westward spread of avian influenza to Wales in the coming months, and increased risk of birds being infected outside, through increased viral survival times and a possible further spread in the range of wild birds carrying the virus.
“Having assessed the evidence, we are taking further preventative action to help protect poultry and kept birds.
“The biosecurity and housing measures we are introducing in Wales will provide additional protection for birds and resilience for our poultry sector. We will continue to keep the situation under constant review.