A mallard duck farm near the north Jutland town of Nibe has been infected with a low pathogenic type of avian influenza H5, according to the Danish veterinary and food administration Fødevarestyrelsen.
An entire flock of 1,200 ducklings will be killed to prevent the virus from spreading and from developing into a highly pathogenic form that is dangerous too humans.
Fødevarestyrelsen has created a surveillance zone with a one kilometre radius around the farm.
All hobby duck shooting within the zone is only allowed with a permission from the veterinary administration.
Avian influenza can be transmitted to humans and other animals through direct contact with infected birds, but when properly handled it does not pose a risk to food safety.
The infection was discovered during a routine inspection carried out as part of prevention efforts against bird flu.
Just two weeks ago, a similar case has been reported at Brenderup farm in western Funen, where 3,000 ducklings had to be put down because of the virus.