Veterinary sources said last night it was highly probable that tests for foot-and-mouth on a suspect sheep from Co Louth would prove positive. There was also a 40 per cent chance that samples from Wexford would be infected.
Preliminary results from the Co Louth farm where the State's second case of the disease is feared, will be available around noon today, according to the Department of Agriculture.
Also expected are the results on samples taken from three sheep at the Slaney Meat Plant, Bunclody, Co Wexford, which had also been sent to the Pirbright Laboratory in Britain for analysis.
The Minister for Agriculture told the daily press briefing yesterday that while a second outbreak of foot-and-mouth in Louth would be "very worrying", an outbreak in Co Wexford would be "frightening".
Mr Walsh said controls were already in place around Co Louth and the Keenan farm at Piedmont, Riverstown, Co Louth, where the suspect animal was found, but should the disease turn up in Co Wexford "it would create enormous problems".
A control zone would have to be established around the county and Brussels would have to be approached to allow regionalisation of another county far away from the original outbreak.
A confirmed case in Co Louth would mean "putting the clock back for another 30 days" and the possible culling of all animals in a three kilometre zone around the farm on the Cooley peninsula.
He said negative samples had been found in samples from sheep in Camolin, Co Wexford, Waterford and Laois and no other samples other than the Co Louth and Bunclody suspects were in the pipeline.
The cull of animals in the Co Louth area now stood at 20,192 sheep, 600 cattle, 30 goats and 15 deer.
Duchas and the Army were continuing their cull of wildlife using helicopters and Army marksmen.
Mr Walsh said it was his belief and the belief of his experts that the source of the case in Proleek was Meigh, Co Armagh, where the first case of the disease on the island was discovered.
"It is my belief that sooner or later we are going to get sufficient information to make the link between Proleek and Meigh."
He said he had been informed by the Northern Minister for Agriculture, Mrs Brid Rodgers, that work would begin today on culling sheep in the corridor in the North where there had been disagreement between the local farmers and the authorities over the slaughter of 2,000 sheep.
In reply to questions, Mr Walsh said he was unaware of any contacts between the Government and Sinn Fein president Mr Gerry Adams about resolving those difficulties nor was he aware that some Northern farmers were seeking immunity from prosecution if they revealed the location of smuggled sheep.
The Minister said that a total of 4,505 sheep and 360 cattle had been culled outside Co Louth in follow-up investigations and tracings involving sheep from the North brought in before the ban on imports was introduced on February 21st.
He said agreement had been reached on tagging every sheep in the State and the farming organisations would be meeting the expert group advising him on controls, to see if any restrictions could be lifted on artificial insemination and other farming activities.
Mr Walsh also announced that he would allow tillage farmers in Co Louth to put their tillage land into EU Setaside.