Currently, there are different rules between species (for example a 5 mile rule for sheep and goat holdings, but no specific distance criteria for cattle holdings).
Ar hyn o bryd, mae rheolau gwahanol ar gyfer rhywogaethau gwahanol (er enghraifft, rheol 5 milltir ar gyfer daliadau defaid a geifr, ond nid oes pellter penodol ar gyfer daliadau gwartheg).