Farmers face an anxious wait to see if a rare pig disease has returned after being wiped out 11 years ago.

Samples have been taken from pigs at a farm in West Sussex which has had contacts with an Essex abattoir where traces of Aujeszky's disease have been discovered.

The abattoir in Essex was where the first traces of foot-and-mouth disease were discovered last year. The outbreak brought havoc to the farming and tourism industries.

However, vets from the Department of the Environment, Food and Rural Affairs (Defra) say Aujeszky's is not in the same league as foot-and-mouth and is transmitted from pig to pig.

A spokesman said: "The results of the samples which have been taken in several counties will take days and even possibly weeks to analyse.

"At this moment we are not treating this as a cause for concern."

The location of the farm in West Sussex visited by vets has not been disclosed.

Signs of the disease include shivering and hind leg weakness. It has not been detected since a slaughtering programme in the early Nineties.

Defra carried out tests during the weekend after routine testing showed the disease in six pigs.

Further tests are taking place in other areas.