Investigating sustainability improvement potential in the Canadian egg industry through integration of life cycle assessment, animal welfare, and operations research

Livestock production systems are associated with large environmental impacts, substantially contributing to the ongoing transgressions of planetary boundaries. Egg production is generally associated with lower environmental impacts than other livestock systems. However, impact reductions must still be realized if eggs are to be part of a sustainable food system. Concurrently, the egg industry must also navigate animal welfare challenges, which are a driving force in ongoing transitions away from conventional cage production systems to alternatives in Canada, and elsewhere globally. This dissertation reports research undertaken to support evidence-based decision making in the Canadian egg industry as it navigates this transition and seeks to contribute to a more sustainable food system. The research is grounded in life cycle thinking and its associated analytical framework, life cycle assessment (LCA), presenting a transdisciplinary integration of LCA with the disciplines of animal welfare science and operations research. Updated baseline LCA models of Canadian, non-organic egg production were developed based on primary data collected from farmers, and best publicly available data for other supply chain activities. These models subsequently supported application of data envelopment analysis, and life cycle optimization to investigate environmental impact mitigation potentials of efficiency improvements on egg farms, and optimization of feed formulations to minimize environmental impacts. Further, a novel animal welfare life cycle impact assessment method was proposed for assessment of laying hens. This method was used with the baseline LCA models to optimize the distribution of Canadian non-organic egg production in alternative housing systems for animal welfare and environmental impacts. Throughout, this research suggests that substantial environmental impact reductions may be realized on Canadian egg farms that outweigh potential increases in production costs. Further, as the housing system transition continues, the environmental- and animal welfare-optimal distribution of Canadian egg production is 100% in enriched housing, regardless of stakeholder priorities for improved environmental or animal welfare outcomes. Overall, this research provides principled decision support to the Canadian egg industry as they continue to navigate this transitionary period, while also making large methodological contributions that may catalyze further transdisciplinary development of LCA methods as a key tool in the sustainability science discipline.