Key trials conducted by Australian Wool Innovation (AWI) into the performance of the clips against mulesing revealed that compared with mulesed lambs, four in 100 more survived when they were clipped.

WA woolgrowers are outraged by the findings, saying they are incorrect, bringing into question the statistics and the accuracy of AWI's trials.

Beverley woolgrowers Max and Luke Edwards said if they were to lose 4pc of lambs at mulesing, or even in a year, they would be out of business.

"I am deeply offended and outraged at a recently released article by AWI that Australian wool growers have a 4pc or more mortality rate from mulesing lambs," Max Edwards said.

"This is absolute rubbish and is just another example of why a lot of WA woolgrowers have very little respect for AWI.

"The kind of information degrades woolgrowers and makes me wonder where they are getting their results from."

As producers of more than 23,000 sheep, the Edwards said they were angered and disheartened over AWI's treatment of woolgrowers in recent years.

"Every producer pays about 50 cents per head to AWI through the compulsory levy and receives nothing in return other than instructions to stop mulesing," Mr Edwards said.

"In our climatic location we cannot run sheep in the numbers we do without mulesing, or using a viable alternative, which isn't yet available.

"AWI still say there will be an alternative by 2010, but I also remember a horrifically expensive shearing machine that should have been available years ago from AWI."

AWI defended itself, saying that while not all farmers may experience the death rates, they were the results of this trial.

"The facts are in these particular trials, four in 100 more lambs survived when clipped," an AWI spokesperson said.

The results will be submitted to the Australian Veterinary Journal for publication and peer review.