R.I. Gen. Laws § 4-6-5

When the records kept by the department of environmental management indicate that eighty-five percent (85%) of the total cattle of the state, excepting steers and calves under six (6) months of age, are free from brucellosis, the state regulatory officials shall require that all brucellosis reactors be slaughtered except calfhood vaccinated animals under thirty (30) months of age.