Several hours earlier, Austria confirmed the first cases of bird flu, also in a pair of swans that died.
Related reading: Prevention of bird flu spreads to humans.
H5N1 virus has recently been found in Italy, Greece and Bulgaria.
A German agriculture ministry official said the dead animals were sent to a laboratory in the UK for further testing. The detection of viruses in Germany will have serious effects.
The Austrian government also issued a regulation restricting the movement of poultry in Mellach, near Graz where two cases of bird flu were known on Tuesday.
Authorities have set up a protection zone within a three-kilometer radius in Mellach and a 10-kilometer oversight zone.
Farmers inside the protected area are not allowed to trade poultry. Farms in the monitoring area may.
