When the percentage of tuberculous cattle within a county, township, municipality or designated part thereof, exceeds one-half of one per centum ( 1/2 of 1%) of the cattle within such county, township, municipality or designated part thereof, the department may impose a quarantine on all the cattle within such county, township, municipality or designated part thereof, during the period of the quarantine. Such quarantine may be continued by the department until such time as the infection is reduced below one-half of one per centum ( 1/2 of 1%) according to the official tests.
N.J.S. § 4:5-53.2