Local health authorities have not yet decided whether all the birds at the farm need to be slaughtered.
A spokesman for the territorial veterinary service earlier said a regional laboratory had identified the lethal H5N1 virus in the dead birds, and that measures were being taken to contain the spread.
A local prosecutor said criminal charges could be pressed against the farm's managers.
The Russian Ministry for Emergency Situations warned last month of a threat of bird flu outbreaks in the Chelyabinsk Region, in the south Urals.
So far, most human cases have been linked to contact with infected birds as the bird flu virus can only be transmitted from birds to human. Experts say it could mutate into a form that spreads easily among humans, potentially sparking a pandemic.
