Female cattle of the beef breeds over 6 and under 18 months of age, for feeding and grazing purposes only, may enter the State or may be shipped from marketing centers or auction markets within the State without test for brucellosis. The Department may require that such cattle be held under quarantine until they have passed a negative brucellosis test and such test is reported to the Department, or until a report of their disposal for slaughter is made to the Department. They may be held in quarantine without test during their feeding and grazing period, which period shall not exceed 12 months from date of entry. Upon application to the Department and at the discretion of the Department such period may be extended for an additional period not to exceed 90 days. When required by the Department, at the expiration of the feeding and grazing period the cattle shall be sold for immediate slaughter or tested for brucellosis at the expense of the owner. The owner shall report such disposition to the Department. Such cattle classified as reactors to an official test for brucellosis shall be sold for immediate slaughter and the owner shall report their disposal to the Department.