EU member states that wish to use EID in cattle must use LF, and thus this applies to Northern Ireland under the Windsor Framework Agreement.
Rhaid i aelod-wladwriaethau yr UE sy'n dymuno defnyddio EID mewn gwartheg ddefnyddio LF, ac felly mae hyn yn gymwys i Ogledd Iwerddon o dan Gytundeb Fframwaith Windsor.