Whenever the department shall find any apiary where queen bees are raised for sale to be free from disease, as defined in section 4:6-1 of this title, he shall furnish the owner with a certificate to that effect. The certificate shall state the date of its expiration. It may be revoked at any time the department shall find evidence of the appearance of disease as defined in said section 4:6-1 in the queen rearing yard.
N.J.S. § 4:6-6