Our current agri-food system needs to undergo substantial transformation to meet the demands for providing sufficiently nutritious food to support healthy people, a healthy environment, and a healthy planet. A key area for future research development to this aim is alternative management systems to drastically reduce waste. There is a growing demand for alternative, efficient and circular waste management solutions for livestock manures and slurries at farm level. In 2016, an estimated 83 million tonnes of livestock manure were produced in the UK alone, which historically has been used on the land as a fertiliser. However, with livestock numbers increasing, excess slurry and manure that cannot be used on the land is now a waste product. Furthermore, in 2021, the Environment Agency issued new guidance on manure spreading which specifically requires the planning of nutrient applications of organic material such as livestock manures and slurries to crops to protect riverine systems from nitrogen and phosphorous pollution. This new guidance has a significant economic and operational impact on slurry and manure management on livestock farms, and therefore highlights the urgency to explore alternative waste valorisation solutions.

Insect-based slurry valorisation could provide livestock farms with solutions to comply with these new environmental regulations, whilst providing innovative economic opportunities such as organic fertilisers and biofuels. Currently a frontier technology, insect waste valorisation requires infrastructure development and associated research activities for its industrialisation and to realise its enormous potential to be transformative to farming, food production and environmental stewardship. Furthermore, robust protocols for raising insects on slurries and manures, alongside appropriate safety dossiers, standards and best practice are essential to support the development of industrial-scale insect bioreactor technology, in addition to the development of appropriate regulation and certification.

We will develop a bespoke research-grade insect bioreactor (iBIO) to be based at the Centre for Innovation Excellence in Livestock (CIEL) National Pig Centre, situated on the University of Leeds (UoL) Research Farm. The UoL Research Farm is currently being developed as a testbed for the integration of technologies that support sustainable approaches to net zero and regenerative agriculture, including waste valorisation and circular economy systems. iBIO will provide insect rearing environments at demonstrator scale to build robust scientific evidence that supports valorisation of a wide range of livestock waste streams. This would be the first research-grade system of its kind in the UK, and as such would allow us to be at the forefront of sustainable agriculture research, a key strategic priority area for the BBSRC. It will also enable us to advance research in other significant areas, including the reduction of livestock emissions, whole system approaches to on-farm circular economy models, minimising pollution of riverine systems, valorisation of livestock waste, and advancement of insect biotechnology. The iBIO will support UoL's ambitions to become the recognised leader in sustainable agri-systems research and innovation in the UK and beyond.

Technical Abstract:
A key area for future research development in sustainable agriculture is alternative management systems to drastically reduce waste, which is a major issue across all areas of the food system. Insect rearing provides an opportunity to recycle waste streams as a feedstock for insects, and so can easily be integrated into existing food systems to help drive a step-change towards more environmentally friendly, sustainable circular economies. Whilst insect rearing has been successfully demonstrated on low-risk feedstocks such as food waste, there is currently a major gap in knowledge on insects reared using high-risk feedstocks such as slurries and manures. The proposed insect bioreactor (iBIO) will therefore enable novel fundamental research on raising insect species on high-risk feedstocks, under high-density monoculture conditions in artificial environments. iBIO will be a walk-in, modular, self-contained unit retrofitted with an environmental control system and Wi-Fi monitoring. The unit will house a racking system for trays and processing equipment, with scope for automation. It will be integrated to complement existing facilities at the University of Leeds Research Farm, and following commissioning, will enable us to advance research in significant areas including the reduction of livestock emissions, whole system approaches to on-farm circular economy models, minimising pollution of riverine systems, valorisation of livestock waste, and advancement of insect biotechnology.