THREE times in the last 20 years, Fine Gael Ministers for Agriculture have taken on the Irish Veterinary Union representing the country's private vets, and three times they have lost. Next week, Ivan Yates makes a fourth attempt, which may be a winner.

In the 1970s Mark Clinton went to war against the IVU on the issue of introducing technicians to carry out brucellosis testing on cows. He lost.

In the I980s, Austin Deasy took on the IVU over bovine TB eradication costs. He lost. So, too, in 1995 Ivan Yates clashed with the vets over rotational testing and lost.

But while Mr Yates lost the battle on rotation testing and the country lost the possibility of millions of pounds worth of EU funding to control bovine TB, he launched the mother of all battles by proposing to privatise the scheme.

Until now the State and its long suffering taxpayers have been paying the country's 1,000 private veterinary practitioners to eradicate bovine TB from the national herd.

The long road to eradication began 40 years, and £1.5 billion, ago and has not been without success. The number of diseased herds has been reduced from 25 per cent in 1958 to 0.5 per cent today.

Nevertheless there is still an unacceptable level of bovine TB in the national herd of seven million animals, a level which could endanger the ability to export if allowed to go unchecked.

Mr Yates's proposal to throw the onus for keeping disease out of herds on to the shoulders of farmers rather than on the State is the most radical reform of the bovine TB eradication scheme in its long history.

Currently the Department of Agriculture arranges the testing of animals on an annual basis and pays the private vet for carrying out the work. From the payment, it deducts the vet's union fee, which it pays to IVU head office.

A report by the Veterinary Council of Ireland, published this week, showed that vets engaged in large animal practices earn over 50 per cent of their in come from TB eradication scheme cheques and meat inspection accounts. The average net income in private practice was estimated to be £40,600 before taxes.

Mr Yates has decided that in future all farmers must arrange an annual test of their herds and pay the vets themselves. Failure to carry out such a test will mean that the farmer cannot trade.

This will, of course, mean that there will be no more Department cheques for the vets and no more fees deducted at source for the Irish Veterinary Union.

But Mr Yates sweetened the pot for the farmers by reducing the levies farmers will have to pay to the Department, down from an estimated £28 million annually to £10 million.

But the sweetest and perhaps the most damaging proposal which he dangled in front of the farmers was the abolition of the compulsory pre movement test that farmers had to arrange and pay for to allow them to sell their cattle.

This test has to be carried out up to 60 days before the animal is sold and it costs farmers more than £3.5 million annually. But, according to the Minister, these pre movement tests turned up only small numbers of diseased cattle for example, less than 500 last year.

At the annual conference of the Irish Veterinary Union in Dundalk last month, the vets seized on this radical departure, which they claim will spread bovine TB right through the national herd. Speaker after speaker at the conference warned that this was the most damaging of the proposals being put forward by Mr Yates.

In a letter to the Farmers' Journal of December 28th, Brendan Gardiner, a vet in Mountbellew, Co Galway, summed up what vets, and indeed many farmers, are thinking.

He wrote "Ian my opinion the scrapping of the compulsory 60 day pre movement test is contrary to all scientific analysis. It may be politically correct but it is not veterinarially correct.

"To allow cattle to become infected on farm A, then allow them to be moved out of that farm, then request the new owner on farm B to carry out a voluntary post movement test defies all veterinary logic.

"These cattle could have travelled many miles through many marts and have contacted many cattle on the way. I could bring you to a village where my practice and a neighbouring practice detected four TB reactors on pre movement tests.

"Subsequent immediate follow up herd tests detected approximately 100 reactors. Under the present proposals all these cattle could be legally traded," he wrote, warning that the good work of the past could be undone.

DESPITE all of this, Mr Yates is likely to announce on Tuesday next at the annual general meeting of the IFA in Dublin that the new scheme will go ahead. He is banking on the support of the Irish Farmers' Association and the Irish Creamery Milk Suppliers' Association.

On the other hand, the IYU has been outflanked and outgunned by the new alliance between the Minister and the farmers. It is being forced this weekend to negotiate on the details of a scheme into which it had no input.

The union itself has already been financially damaged to the tune of £50,000 by its strike last year over rotation. No testing meant no union fees.

In 1996, if the scheme is accepted, the union will have to extract its fees from its own membership, which will in turn have to extract payment from the farmers, who are estimated to owe vets over £30 million for other work already done.

Earlier this week the secretary of the Department of Agriculture, Mr Michael Dowling, held discussions with the IVU on operating the new privatised system. The IVU sought certain assurances, and warned farmers that privatisation would mean higher charges for the tests and VAT registration for all farmers.

It appears that the IVU is facing a fa it accompli, and the farmers an entirely new system, in this latest twist in the saga of bovine TB eradication.