Livestock on an English farm that were tested after showing signs of foot-and-mouth do not have the disease, Britain's chief veterinarian said Saturday.

"The latest tests on the farm to the east of the surveillance zone are negative," chief vet Debby Reynolds said.

The result is evidence that the highly contagious livestock ailment has not spread beyond the small area where it was first discovered last week.

Reynolds said late Thursday that cows in a second area of the southern England county of Surrey had shown "mild clinical signs of infections" and were being tested. Officials established a new 1.8-mile exclusion zone around a farm previously unlinked to the outbreak.

She said Saturday that farmers should remain vigilant for signs of disease.

"It is day eight, very early in foot and mouth disease 2007, so relentless vigilance amongst the farming community is the order of the day," Reynolds said.