Some 200 samples taken Thursday, a day after bird flu was found at the farm in Murighiol, tested negative for the potentially deadly H5N1 virus, the head of the National Veterinary Health Agency ANSV Radu Roatis said.
But tests were still being conducted on a cat found dead at the farm to determine whether the animal died of bird flu, said Ioan Lazar, also from ANSV.
In the meantime, health safety measures around the farm will be maintained, Roatis said.
Veterinary health authorities will continue to monitor poultry in the vicinity of the farm and test migratory birds, which could be the source of the virus, he added.
The Institute for Diagnosis and Animal Health confirmed Wednesday that the H5N1 virus had been found at the small farm in Murighiol and all its poultry was immediately culled.
Romania has been among the European countries worst hit by bird flu, with some 55 outbreaks of the disease in 2005 and another 150 in May 2006 in breeding farms in the centre of the country.
Last year, some 1.1 million birds were slaughtered to contain the virus.
The virus is regarded as a global threat because scientists fear it could mutate into a form that is easily spread among humans, leading to a pandemic with the potential to kill millions.
Worldwide the H5N1 virus has killed 192 people out of 319 infected patients since reappearing in late 2003, according to a World Health Organisation toll published in July.