THE chief vet handling foot-and-mouth in the North-East has spoken of the importance of blood sampling for lifting Form D restrictions.

Once an individual farm has been found to be infected, all other farms within a 3km radius are automatically placed under the restrictions, which ban the movement of animals, on or off farms, and places strict hygiene conditions on the movement of people, vehicles and machinery.

The restrictions cannot be lifted until DEFRA vets are confident there has been no spread of the disease to any other animals within the 3km radius.

To do that, a programme of inspections and blood sampling must be done to determine that the animals have not been exposed to foor-and-mouth.

Mr Charlie Moir, divisional veterinary manager at the FMD control centre in Newcastle, said the authorities had to be absolutely confident that there was no disease left in the particular area to start the spread again.

"For this we must identify all premises with susceptible stock and examine sufficient animals from each farm in the restricted area," he said, "Blood samples are also collected."

For cattle it is generally sufficient to inspect and clinically examine any suspect animals.

"For sheep, however, we must carry out a combination of inspection, examination and blood testing of a representative sample in the separate groups under which they are managed in flocks," said Mr Moir.

The leader of the sampling team will discuss livestock holdings and management systems with farmers and decide how many and which of the animals must be sampled. They will also note farm holdings and rented fields on a map and check movement and medicines record books.

Once all the samples are taken, they are sent to the Institute of Animal Health at Pirbright for testing and analysis.

Only when all samples from all premises in the zone have been analysed and confirmed as negative can the lifting of Form D restrictions even be considered.

The process takes longer if all the necessary animals on the premises within the zone cannot be identified; if records are incomplete and handling facilities are poor. A lack of co-operation by a farmer in ensuring full inspection and sampling can cause delays as well as inconclusive results and new outbreaks within the zone.

If any of the inspections or tests proves positive, the situation will be reappraised.