Tests carried out on the dead swans found in Counties Down and Antrim show they did not die from bird flu, the Department of Agriculture has revealed.
The dead swans were taken away for further tests
Northern Ireland chief vet Bert Houston said other swans recently tested were not infected with H5N1.
Routine tests were being carried out on dead swans found on Thursday at Moira and near Randalstown.
The agriculture minister has said Northern Ireland is prepared to deal with any outbreak.
Lord Rooker's comments followed the news on Thursday that a swan found in Scotland was carrying the H5N1 strain.
On the same day, council workers found a newly-dead swan on the River Bann near Portglenone. Later, a second partly decomposed bird and two badly decomposed swans were found nearby.
Officials also recovered the carcass of a dead swan from a grassy field near Moira.
Bert Houston outlined what contingency plans had been made
Mr Houston said there was a contingency plan in the event of avian flu being found in Northern Ireland.
"It will involve us setting up a series of command structures, getting a local exotic disease centre placed on the ground, we will put in 3km protection zones, 10km surveillance zones and apply all the control measures required by the European Commission," he said.
Meanwhile, a spokesman for Dungannon-based poultry company Moy Park, which deals with about 350 farms across Northern Ireland, said "intensive security" had been in place "for at least two years".
Gareth Jones said there was "no unnecessary movement" on poultry farms, and all major producers were "united in keeping this thing at bay".
Mr Jones said he felt people understood that "contracting bird flu does not happen from eating chicken or eggs".
On the wider issue of bird flu preventative measures, he said testing "has been going on for many months, in excess of 1,000 birds, and they've all proved negative".
"The public should be reassured that this testing is happening. I was surprised to read that it was only (a small number of) birds being tested, I thought it was a lot more."
The H5N1 virus does not at present pose a large-scale threat to humans, as it cannot pass easily from one person to another.
But experts fear the virus could mutate to gain this ability, and in its new form trigger a flu pandemic, potentially putting millions of human lives at risk.
The Department of Agriculture has set up a special phone line. It is 028 90 524999. The advice is that you should ring if you spot a dead swan or other waterfowl, or large numbers of dead birds.