B.AHE.0264-Peer review of research undertaken in the support of the development of the NUMNUTS® device
A recent review has confirmed that NUMNUTS is an effective device to reduce pain in lambs from castration and tail docking.
| Project start date: | 29 March 2019 |
| Project end date: | 29 May 2019 |
| Project status: | Completed |
| Livestock species: | Sheep |
| Relevant regions: | National |
Summary
Castration and tail docking are important husbandry procedures for sheep in Australia. However, the current method of rubber constrictor rings causes pain and discomfort to young lambs. NUMNUTS is a device designed to mitigate pain associated with castration and tail docking of lambs by delivering a dose of anaesthetic when the ring is applied.
This project supported a review of the broader literature around pain associated with these procedures, and the NUMNUTS projects undertaken by MLA. Subsequently, the reviewers summarised the evidence around pain mitigation for both the tail docking and castration of lambs and made recommendations for further work that may be required to fill knowledge gaps and facilitate adoption. The literature review provided evidence that the current methods of castration and tail cause pain and distress in lambs; however, the duration of pain associated with these procedures was not well investigated. The review of MLA funded projects concluded that there is some evidence that the use of NUMNUTS for tail-docking reduces the pain associated with marking.
A recommendation was made for more targeted research to increase adoption through enhanced confidence, particularly concerning the benefit of using the device for castration. In addition, reviewers suggested undertaking large, randomised, field-based studies to build confidence. The reviewers also identified further research areas, including the effectiveness of pain relief beyond three hours and the potential value of using multiple analgesics.
Objectives
There were four objectives of the review:
1. Carry out a peer review of MLA funded project reports and papers resulting from research supporting the development of NUMNUTS®.
2. Undertake a literature review of research that specifically relates to the use of local anaesthetics to relieve acute, immediate pain caused as a result of the castration and tail docking of lambs.
3. Resulting from the desktop study findings, provide an opinion as to the veracity of research undertaken and the legitimacy of claims for pain relief for both the tail docking and castration of lambs. Further, to evaluate the likelihood of adoption success.
4. Provide recommendations on further research (if any) that may be required to fill gaps in knowledge on the ability of local anaesthetic to provide consistent and unequivocal pain relief for both tail docking and castration of lambs.
Key findings
The review included five MLA funded research projects, concluding that there was evidence that NUMNUTS provides pain relief from tail-docking and castration. In order to build confidence, more targeted research with diverse measures of pain should be conducted.
The review of the published literature included 47 papers and found evidence that castration and tail docking using a rubber ring does cause pain in lambs. Administering a combination of local anaesthetics at multiple sites was found to be effective. Further, it was found that pain assessment should use multiple objective and subjective parameters.
Benefits to industry
Castration and tail docking are routine procedures to prevent flystrike, and in males, unwanted mating and behaviours that jeopardise safety when handling. Castration and tail-docking are commonly performed using rings that cause some pain and discomfort to lambs, risking the industry’s social license. There has been considerable investment from MLA into the NUMNUTS device, and this project reviewed this previous investment to ensure that the claims for pain relief are legitimate and that there is accurate information available to underpin future endorsement, investment and adoption decisions.
Future research
Future research should consider addressing ten factors:
• the optimal timing for administration of preventive analgesia
• the ideal sites for distribution of local anaesthetic for complete desensitisation of the tail or scrotum and testes
• the optimal dose of local anaesthetic
• the value and composition of multimodal analgesia for lambs that includes analgesia drugs from multiple classes
• development and validation of pain assessment strategies for lambs
• the method of castration and tail docking and its impact on the time for tissue healing following castration and tail docking
• large randomised control field-based studies
• the impact of wound infection and the time to recovery
• establishment of clear research questions and hypotheses and appropriate study design
• power calculations during study development
More information
| Project manager: | Christine Purdy |
| Contact email: | reports@mla.com.au |
