4-year PhD Studentship: Assessing long-lasting pain following hot-iron disbudding in dairy calves

Although freedom from pain is a key pillar of animal welfare, painful procedures are still common on most dairy farms. For instance, despite being painful1, hot-iron disbudding is still performed on the vast majority of calves. Although the procedure may be performed in a way that limits intra-operative pain (using a combination of anaesthetics and analgesics), recent reports suggest that calves may experience pain for days or weeks after the procedure2,3. However, limited information is yet available on the long-term emotional impact of the procedure and on ways to mitigate it. This PhD project will therefore aim to 1) develop the tools to assess the emotional component of long-lasting pain and 2) develop new ways to tackle pain over long periods of time. For this, we will develop methods based on pain relief as animals are expected to work to access pain relief solutions if they experience pain. These will include novel explorations of the use of cold therapy as a means of providing non-pharmaceutical pain control. We expect that this project will deepen our understanding of what calves’ experience after hot-iron disbudding and contribute to inform on potential innovative and low-cost solutions to tackle the pain.

Aims and objectives

• Develop methodologies to assess long-lasting pain following hot-iron disbudding

H1: Calves in pain should seek and work for access to pain relief for as long as they are in pain.

H2: Calves in pain should feel better (assessed via judgment bias and conditioned place preference tests) when receiving an analgesic.

• Assess the efficiency of cold therapy to mitigate pain following hot-iron disbudding

H1: Animals should experience less pain when they have continuous access to cold therapy.

Methodology

Hot-iron disbudding is typically performed at a young age in dairy calves. We will use animals produced at the UoB’s John Oldacre Centre Wyndhurst Farm (Langford) to study the effects of disbudding using a range of established and innovative techniques. For instance, the conditioned place preference and the judgment bias tests will be used to explore the effects of different pain relief methods over time. Motivation for pain relief will also be explored using techniques based on motivational trade-off where animals must give up something pleasant to access pain relief; the more they are willing to give up the more they are motivated to access pain relief, the more they were in pain. Animals will also be tested for their motivation to play or to perform social behaviours as these can reflect on changes in mood states following disbudding. The student will develop skills in experimental design, developing and conducting state-of-the-art behavioural tests in large animals. He/she will also develop proficiency on data analysis, scientific communication, application and dissemination of animal welfare research. These skills will be transferrable to other species and research questions in the wider fields of animal science and sustainable agriculture.

Supervisors: Mike Mendl (primary supervisor), Benjamin Lecorps, nan

Funding available

This project is open for Bristol PGR scholarship applications (closing date 1st December 2023)

The Bristol PGR scholarship funds tuition fees, the costs of carrying out your research and a maintenance stipend (at the minimum UKRI rate) for the duration of a PhD (four years).

How to apply for this project

This project will be based in Bristol Veterinary School in the Faculty of Health Sciences at the University of Bristol. Use this information to search for the relevant programme in our online application system.

Please visit the Faculty of Health Sciences website for details of how to apply, the information you must include in your application, and for information about our online Application Workshop to help you submit a competitive application.