American veterinarians are to be briefed this weekend on new research which shows the clips designed to reduce susceptibility to flystrike in Merino lambs have far less impact on the health and welfare of the lambs compared to that of mulesing.
The research program, funded by Australian Wool Innovation Limited (AWI), was conducted by an independent team of veterinary scientists from the University of Sydney.
The results of the study will be presented to the American College of Veterinary Pathology annual conference in Texas this weekend by PhD student Michelle Lepherd.
The study compared the local and systemic health impact of mulesing on young Merino lambs with alternative methods of:
• Reducing skin wrinkles and
• Increasing bare areas to improve blowfly strike resistance.
The study team included senior lecturer in veterinary microbiology, Dr Katrina Bosward, veterinary pathologist, Prof Paul Canfield, and veterinary surgeon associate professor, Geraldine Hunt.
Study leader Dr Bosward says wrinkled skin, dense thick wool and moisture around the breech and tail areas of Merinos are known to create a “blowfly breeding paradise”.
“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 Merinos,” Dr Bosward says.
“We took this one step further and looked at what was happening deeper down in the skin and observed what effect the clips were having on the skin microscopically.
“At the same time as assessing effectiveness of the clips at reducing the excess skin around the breech area, we subjectively measured a wide range of variables that indicate the lambs’ degree of discomfort as well objectively measuring the body systemic response to the treatment.
Subjective measures of discomfort included monitoring appetite loss and changes in behavior such as tail swishing and reluctance to walk or lie down, according to Dr Bosward.
“The objective measures included measuring weight gains as well as blood changes, “ she says
“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.
“Overall the clips had only relatively mild local and systemic health impacts compared with mulesing.
“The clips produced well healed linear scars, with reasonable tightening of the skin that may be adequate for the prevention of flystrike.”