The Animals (Post-Import Control) Order 1993

15.  After the isolation period, the animals shall not be permitted to leave the isolation premises unless authorised by the Divisional Veterinary Officer in writing, which authorisation shall not be given until all imported animals on the isolation premises have passed the final EBL test; except that where pregnant animals calve more than 170 days after importation, release of other imported animals in the isolation premises is at the discretion of the Divisional Veterinary Officer. Any animals which have calved in the isolation premises may be released at the discretion of the Divisional Veterinary Officer when all the animals in isolation premises have met the EBL testing requirements.