Another 50 animals believed to have been smuggled in from Northern Ireland were found in raids on farms in Co Tipperary on Saturday.
The raids on nearly 20 farms were carried out by the Department of Agriculture's special investigation unit, backed up by gardai.
This brings the number of animals found in and around north Tipperary without proper identification tags in the last month to nearly 120.
The hunt for illegally imported animals has been intensified as another case of foot-and-mouth disease was confirmed in Northern Ireland, on a farm in Ardboe, Co Tyrone. This is the fourth confirmed case in the North.
Sources close to the investigation said it had been acting on information gathered since the investigation began in the middle of last year and from telephone calls made to a confidential line set up by the Department of Agriculture last week.
The president of the Irish Farmers Association, Mr Tom Parlon, said the discovery of animals smuggled in from the North was "worrying and disturbing". He said the extent of those illegal animal movements had come as a surprise to him, and he lived very close to Tipperary.
"I understand that the guards have very good information and I understand that the farmers in the areas have been forthcoming with a lot of information.
"I understand that they have identified a number of godfathers who have been involved in this activity over the last year and they are smugglers. Previously they were involved in diesel and petrol and tyres, and cigarettes and alcohol and you name it, and unfortunately smugglers find an outlet," he said.
"If you are selling something at half price there are people there," he said. He accepted that farmers had been buying smuggled animals.
"At the time they bought them it was pre foot-and-mouth and I would say those farmers are extremely concerned and that is why they are taking the very drastic action of turning them out on the road, of slaughtering them and burying them on farms," he told RTE's This Week programme yesterday.
Mr Parlon said he had called for the full rigour of the law to be used against anyone - processor, farmer or dealer - involved in such activity and that would be the IFA's line. "There is no comfort or no safety within IFA. We would support the Government and the Minister very strongly in taking a very tough line," he said.
The Northern Ireland Minister of Agriculture, Ms Brid Rodgers, said she was "clearly disappointed" at the new outbreak, but it was not unexpected because the farm adjoined the Donnelly holding, where the second outbreak in the North had been found. The animals had been culled last week as it was in the 1km zone.
The results of tests on sheep slaughtered at the Camolin, Co Wexford, plant last week are expected from Pirbright laboratory in England in the next two days.