P.PSH.0818 - Improving animal welfare in the red meat industry - pain relief

Summary

The application of topical anaesthetics to inhibit pain sensation requires supplementation of longer acting analgesics to reduce sensitisation of wound pain and improve overall welfare outcomes. Options for practical administration of analgesics and the potential for long-acting analgesics to provide prolonged therapy will be investigated, including development of a novel self-medication strategy for use in extensive farming systems. Furthermore, emerging evidence of the efficacy of these therapeutic agents for a wide range of husbandry procedures suggests the potential for a pain management regime to be applied to other painful conditions in sheep and cattle. The outcome will provide producers with an affordable, efficacious and practical protocol for delivering pain relief on farm.

Objectives

This project will investigate novel approaches to address pain associated with painful husbandry procedures in cattle and sheep. The proposal builds on previous work investigating pain assessment and amelioration of pain to improve livestock welfare and provide a positive impact on consumer perceptions of meat production. The application of topical anaesthetics to inhibit nociception requires supplementation of longer acting analgesics to reduce sensitisation of wound pain and improve overall welfare outcomes. Options for practical administration of analgesics and the potential for long-acting analgesics to provide prolonged therapy will be investigated for use in extensive farming systems. Furthermore, emerging evidence of the efficacy of these therapeutic agents for a wide range of husbandry procedures suggests the potential for a pain management regime to be applied to other painful conditions in sheep and cattle.

This project will also investigate novel and routine markers of pain to improve pain assessment and importantly analgesic efficacy. A multimodal approach to pain measurement and analgesic efficacy will be used based on electrophysiology and novel biomarkers identified through recent work. The outcomes will focus on the benefit of pain management to overall welfare and productivity, thus benchmarking gains from pain management with the major MISP outcomes of "fit for purpose" and QA of animal welfare. This proposal also complements the USYD proposals Measurement and Mortality submitted under the Strategic Partnership for Animal Welfare.

Key findings

Pain Assessment:
Studies were conducted to develop and trial facial grimace scores in calves and lambs. These methods for monitoring and measuring pain response were found to be highly variable and as such were not further developed in the project. A large-scale study undertaken in conjunction with project P.PSH.0819 ‘Objective measures of welfare’ using ear tag technology to monitor pain responses was found to effectively demonstrate both short-term and long-term effects of castration and dehorning on weaner cattle. Individual biomarkers identified in previous literature reviews were also examined however provided inconsistent conclusions in regard to pain responses.

Pain Amelioration:
This project demonstrated the inflammatory and wound healing response resulting from routine husbandry procedures can last several weeks, particularly for methods utilising rubber rings, resulting in additional welfare impacts in some instances, such as secondary wound infection. The project also found that current analgesic options do not appear to have animal welfare or production benefits.
This project has demonstrated the feasibility of extending pain relief using a modified release injectable formulation of meloxicam and through meloxicam-medicated feed. These options offer potential solutions to address the long-term pain associated with painful husbandry procedures, though they require further research to elucidate commercial viability and safety.

Benefits to industry

The key outcomes from this program further highlight the need for industry to address long-term pain associated with husbandry procedures such as dehorning to adequately address animal welfare. This may be achieved using existing therapeutics in the form of a slow release injectable or feed additive.

MLA action

MLA will continue to invest in projects that focus on improving animal health and welfare through pain mitigation.

Future research

Further research is required to develop strategies to provide long lasting pain relief and wound management following aversive husbandry procedures. The development of a modified release injectable drug would allow producers the option to provide a one-time long-acting analgesic. Likewise, the development of feed additives to address pain could also provide producers with an alternative to providing long-acting analgesia, within suitable production contexts.