The lure of the dairy gravy train has seen suckler cow numbers fall by up to 20pc in some eastern and south-eastern counties.
The county-by-county breakdown confirms that many younger farmers are opting to switch to dairying or calf-to-beef systems.
Beef cow numbers nationally have fallen almost 6pc over the past four years.
Figures from the Department of Agriculture AIMS database show there were almost 917,000 beef cows at the end of 2014 but this number had fallen to 864,500 last month.
The financial pressures of suckler farming in the west coast, where weather has also taken its toll, were evident. However, the sharpest decrease has taken place in eastern and south-eastern counties.
Suckler numbers in Waterford have fallen by 18.9pc from 22,400 to 18,240, while Kilkenny is down 11.9pc and Cork 8.4pc.
Some of these counties have also seen prominent beef men such as former IFA livestock chair Michael Doran make the switch.
The figures show suckler numbers are down 4.4pc in the border, midlands and west regions, dropping from 485,400 to 464,600 over the past four years.
There was an 7.5pc decline in Donegal - 35,700 to 33,000.
However, Teagasc head of drystock Pearse Kelly said the overall national drop in numbers was lower than initially feared. "Six per cent is not a massive move, it is not the Armageddon that people thought might happen after quotas," he said.
"The BDGP payment is possibly stopping some people from reducing cow numbers."
With the ongoing weather hardship in the west, he said "some are switching to lighter stock beef cattle or to sheep".
Amid calls for a €200 a cow payment, Agriculture Minister Michael Creed told last week's AGM of the IFA that by and large there has "not been the exodus" as predicted. He warned a coupled payment might undermine the BDGP scheme and would cost €200m a year or 18pc of the basic payment. The ICSA's Eddie Punch said it was inevitable that the ending of milk quotas would lead to some loss of sucklers.
"It is also clear that it is the largest scale suckler farmers that are the most likely to convert to dairying for reasons of economic logic, but this has an exaggerated impact on the figures in counties like Cork."
Mr Punch questioned the wisdom of a coupled payment for sucklers, arguing that a move to paying on meat yield and guaranteeing top prices for heavier U and R grade carcasses would be far more effective.
"Trying to artificially boost suckler numbers is self-defeating if we do not have a strategy for a viable price," he said.