Eastbio Environmental trade-offs of parasite control in sustainable livestock systems

With demand for increased food production coupled with a need to reduce Green House Gas (GHG) emissions and conserve biodiversity, there is growing pressure to balance productivity with environmental sustainability in livestock systems.

 The environmental impacts of cattle are widely acknowledged. Around 40% of anthropogenic methane emissions are attributed to agriculture, a majority of which is from enteric fermentation in livestock. Helminth parasites (roundworms and fluke) are a major constraint on sustainable livestock production worldwide, with most farmers controlling infections using chemical (anthelmintic) treatments. Our team have shown that parasitic roundworms of lambs can drive a 33% increase in methane yield. The direct impacts of parasitism on methane yield in cattle have never been measured, despite cattle being responsible for nearly ten times more global emissions than small ruminants. This studentship will produce the first empirical measurement of the direct impacts of parasitism on cattle methane yield. This will be achieved by running controlled challenge experiments at SRUC’s Greencow facilities, utilising Moredun’s established Ostertagia ostertagi infection model. It will then characterise the GHG mitigation potential of controlling disease using anthelmintic drugs. This will be achieved by parameterising an existing process-based model with empirical data from the parasite/emissions experiments to determine the true impact of parasitism on CH₄ per kg of meat and the GHG mitigation potential of anthelmintic usage.

 In addition to the environmental benefits of reducing livestock GHG emissions and improving production efficiency, disease control can have broader ecosystem level impacts. There is increasing concern about the fate of anthelmintics excreted from treated animals, with compounds used to control parasites having the potential to negatively impact on soil fauna. This studentship will also determine the impacts of anthelmintics on soil biodiversity. This will be achieved by assessing impacts of anthelmintic treatment on parasitological, production, and ecological (e.g. soil microbiome and invertebrate fauna) parameters, as part of an ongoing longitudinal grazing study where grazing strategies and anthelmintic treatment choice are assessed.

Through exploring both the GHG mitigation potential of anthelmintics and the impacts of anthelmintic residues on invertebrate biodiversity, this studentship will examine the environmental trade-offs of anthelmintic use in sustainable grazing systems.

 Working in a cross-disciplinary team, the studentship will include placements at SRUC, BioSS, and Moredun, providing training in cutting-edge practical, computational, and analytical techniques. This will prepare the student to address the multidisciplinary challenges of environmental change, animal health, and future food security. 

 HOW TO APPLY

Application instructions can be found on the EASTBIO website- http://www.eastscotbiodtp.ac.uk/how-apply-0

1)     Download and complete the Equality, Diversity and Inclusion survey.

2)     Download and complete the EASTBIO Application Form.

3)     Submit both to SRUC, [Email Address Removed].

A complete application must include the following documents:

• Completed EASTBIO application form
• 2 References (to be completed on the EASTBIO Reference Form, also found on the EASTBIO website)
• Academic Qualifications
• English Language Qualification (if applicable)

Unfortunately due to workload constraints, we cannot consider incomplete applications. Please make sure your application is complete by Monday 5th December 2022.