This is in recognition of the lower risk posed by those herds, which have not had TB for ten or more years.
Rhoddir achrediad lefel 10 CHeCS i wartheg a anwyd ar y daliad yn unig, Mae hyn yn cydnabod bod y buchesi hynny, nad ydyn nhw wedi cael achos o TB ers deng mlynedd neu ragor, yn peri llai o risg.