Clips
The concept of clipping developed from the idea that it may be possible to create a similar effect as mulesing without creating an open wound and resolving the pain issues.
The technology:
The clips are attached to flaps of skin that would be removed during mulesing. The clip closing pressure on the flap of skin prevents blood flow to that part of the skin. The lack of blood supply causes the flap of skin to wither and both the clip and the skin flap typically fall off within a couple of weeks to leave a closed linear scar. It is a similar effect to the elastrator ring used on the scrotum and tail.
There is no open wound at any time during the process. Another advantage of the clip method is that the amount of skin ‘stretch’ can be clearly seen during the process of applying the clips, making it easier to achieve the optimal bare breech result.
If it suits a grower’s management practices, the lambs can be yarded and the clips removed. The clips can be re-used the next season. Otherwise, the clips will drop off in the paddock. However, the ideal solution will eventually be a biodegradable clip. Various materials have been trialled and an international search is continually undertaken to see whether new, cost-effective biodegradable materials that would suit the clips are being developed.
Progress:
Work on the clips began in early 2005. In 2006, the work concentrated on identifying the optimal designs, production materials and methods of application, as well as evaluating how well the process works and the advantages in terms of animal health and welfare.
Initial field trials investigated different designs and materials. Five further field sites in NSW were established to measure the effectiveness of clips compared to mulesing over a period of 18 months. Another series of field trials started in June 2006 to confirm the practicalities of using the clips across several States and different sheep types.
In the early production trials, there were instances of clips moving or falling off. The problems have been overcome through modification of the clip design. With increasing experience, operators are developing improved application techniques which are also contributing to increased retention and effectiveness.
In 2007, Australian woolgrowers were invited to take part in broad scale commercial trials of the clips – over 1100 woolgrowers responded with offers to trial the clips.
AWI is currently immersed in the data entry and analysis process of the almost one million items of data generated by the 2007 clip trials.
As would be expected from 200+ sites across Australia, the results are variable. Early indications are that the clips are working towards producing an outcome similar to mulesing. A very positive sign is that a number of participants in the 2007 trial have requested access to clips for their entire 2008 lamb marking.
A full analysis of the trials will be available in late June 2008.
An independent review in January 2008 by the Australian Veterinary Association (AVA) of AWI R&D on mulesing alternatives stated:
“The development of clips is progressing well and the first results of the broad scale commercial trials conducted on producers’ properties are indicating satisfactory performance. Some producers who have trialled the clips on their properties have been impressed with the results and have reported that they feel confident that they could cease mulesing and adopt the clips as the principal means of preventing breech strike.”
The AVA concluded:
“We believe that the progress made so far on the bloodless skin wrinkle removal (clips) continues to indicate that it will be a viable alternative to mulesing before the project deadline of 2010 for the phasing out of mulesing.”
The AVA independently reviews AWI’s progress in R&D on mulesing alternatives on a quarterly basis and publishes a report after each review. AWI fully cooperates with this review.
Animal welfare aspects
A comprehensive animal welfare assessment provides significant support for the use of clips as an alternative to mulesing. Director of the Animal Welfare Science Centre (AWSC), the University of Melbourne’s Professor Paul Hemsworth, has assessed the animal welfare aspects of ‘breech and tail’ clips:
The AWSC specialises in studying the behaviour and welfare of farm and companion animals and the influence of human-animal interactions on animal welfare and productivity. The AWSC has conducted two separate studies of mulesed, clipped and no-treatment lambs: the first focused on the behavioural responses and the second study focused on behavioural, physiological and fitness effects to gain an insight to the welfare aspects of the clips.
Professor Hemsworth says the key conclusion is that:
“The clip treatment has only a mild impact on the biology of lambs and thus the welfare risks are considered relatively minor.”
The research included comparisons of key physiological factors in the ‘stress response’ such as plasma cortisol and haptoglobin levels, and behavioural and fitness factors such as posture, locomotion, and time spent feeding and lying-down. Professor Hemsworth also noted that the lambs treated with clips often responded in a similar manner to those in the ‘control’ treatment – in which lambs were held in a mulesing cradle for the same time as clipped animals, but not mulesed.