Bridging the Gaps: Systems-level approaches to antimicrobial resistance
Sleeping with the (AMR) enemy: Evaluating the impact of separated cattle slurry on the environment, and within cattle bedding on antimicrobial resistance and co-selective drivers
Martin Green (School of Veterinary Medicine and Science [SVMS]), Bobby Hyde (SVMS), Jon Hobman (Biosciences) Dave Barrett (Pharmacy) and Rachel Gomes (Engineering)
The issue
Dairy cows need to be housed with comfortable dry bedding, especially during winter months. Recently farmers have begun to use separated recycled manure as a ‘green’ alternative to straw, synthetic mattresses, wood shavings and other, older, bedding types. To create recycled manure solids (RMS) bedding farms separate the liquid and solid parts of the waste, following a strict set of controls set out by the Department for Environment, Food & Rural Affairs (DEFRA). We want to know more about the risks involved in using this bedding type, specifically whether the presence of manure in the bedding environment might change the rate of antimicrobial resistance (AMR).
The research
Collaborators with expertise in veterinary medicine, microbiology, engineering and mathematical modelling are exploring slurry samples from unprocessed slurry through to dry stored RMS. They will examine the prevalence of e-coli bacteria as a sentinel species (indicator of the presence of disease) and look at the e-coli bacteria at every stage of the slurry from unseparated to liquid, solid and after a period of several weeks of storage.
The impact
Researchers want to:
- Better understand the effects of treatments on the survival of a sentinel AMR bacterial species in solid RMS compared with the initial slurry. Existing research suggests that the process of creating dry bedding will reduce the rate of AMR in slurry.
- Determine optimal treatment to reduce/eliminate bacteria, especially when slurry is applied to land.
- Understand whether changing the dryness/temperature of the slurry makes some bacteria more tolerant to dessication and/or temperature extremes and therefore harder to kill.
- Understand what happens to metal and antibiotic pollutants normally found in slurry.
The findings of this work will go on to inform the national policy around the use of RMS bedding and will also add to the picture of RMS and its safety for use across the rest of Europe and the Americas.
If you are interested in finding out more about this research or about Bridging the Gaps please be in contact with Harry Moriarty h.moriarty@nottingham.ac.uk in the first instance.