Clearly there are serious shortcomings within the compensation and appeals system which need to be addressed

Billy Bell MLA

The chairman of the PAC, Billy Bell, said he was greatly concerned at the number of deliberate infection cases.

"We regard this as a very worrying development which DARD must get to grips with," he said.

"Clearly there are serious shortcomings within the compensation and appeals system which need to be addressed."

However, the Department of Agriculture has rejected criticism by the assembly's public accounts committee of its handling of brucellosis.

Agriculture minister Brid Rodgers said the department was tackling the threat rigorously and had zero tolerance of fraud.

Meanwhile, the president of the Ulster Farmers' Union, Douglas Rowe, said if there was fraud farmers should be prosecuted but he felt more publicity was needed about the dangers of disease.

He said: "The department should probably have made people more aware of, particularly, the rise of instances of brucellosis over the past couple of years."

Brucellosis is a highly infectious disease which causes cows to abort.

It also poses a risk to people working with cattle, leading to recurring bouts of fever.

Valuations

The committee is also critical of the sharp increase in compensation paid to farmers for cattle culled.

The compensation bill to taxpayers has spiralled from �200,000 to more than �22m over the past five years.

Last year more than �9m was paid out.

The committee is also concerned about valuations being placed on infected herds.

In one case the department's original valuation of �375,000 rocketed to �1.4m on appeal only for an auctioneer from Britain to finally decide that the animals were worth �275,000.

The department is criticised for its slow response to the brucellosis threat and in failing to crackdown on people suspected of wrongdoing.

The department has promised to deliver a strategy to combat fraud and to review its brucellosis eradication programme.