Australian Wool Innovation (AWI) commissioned the study, which was conducted by a team of veterinary scientists at the University of Sydney.

The research examined the effects the clips had on Merino lambs and compared these effects with those of surgical mulesing.

“To the naked eye, the plastic clips have been shown by us and others to significantly reduce the wool cover around the tail and breech, a major factor associated with flystrike in Merino.

"The clips produced well healed linear scars, with reasonable tightening of the skin that may be adequate for the prevention of flystrike,” senior lecturer in veterinary microbiology, Dr Katrina Bosward said.

An AWI spokesman said he assumed the research was conducted without pain relief.

The study assessed the level of discomfort shown by the lambs by blood testing and weight changes as well as watching for behavior such as tail swishing and a reluctance to walk or lie down.

“The results confirmed that mulesing causes very significant discomfort and other negative health effects at lamb marking. The negative impacts of using the clips were significantly lower than they were for mulesing.” Dr Bosward added.

The findings are to be presented to American veterinarians this weekend.

Australian PhD student Michelle Lepherd will be briefing her US colleagues at the American College of Veterinary Pathology annual conference in Texas.

Australian RSPCA is yet to endorse the clips as a viable alternative to mulesing.

The organisation which brought the issue to the world’s attention, the People for the Ethical Treatment of Animals (PETA) have long claimed the clips inflict too much pain for the technology to be acceptable.

AWI has stated the clips are only seen as an interim solution until the industry finds a more cost effective and practical solution, with breeding for barer breeches and plainer bodied animals as the long term solution to ending surgical mulesing.

Widespread on-farm trials across Australia have shown the clips have a mixed effect, being more effective at increasing the bare area around the breech and reducing flystrike on plainer bodied animals than on more wrinkled bloodlines.