Environmental impact mitigation potential of increased resource use efficiency in industrial egg production systems
Ian Turner, Davoud Heidari, Nathan Pelletier
Abstract
Much of the global egg industry is currently transitioning from conventional cage to alternative (i.e. enriched cage, single- and multi-tier free run, free range, and organic) housing systems. While this transition is primarily motivated by animal welfare concerns, it also has significant potential to alter the environmental footprint of egg production, which is the fastest growing livestock sector worldwide. Understanding the benefits, impacts and improvement opportunities characteristic of alternative systems is hence imperative to ensuring net-positive sustainability outcomes. This requires attention to current resource efficiency levels, key variables that influence efficiency, as well as the environmental impact mitigation potential of efficiency gains for specific interventions and housing systems. The current analysis reports a joint application of data envelopment analysis (DEA) and life cycle assessment (LCA) to industrial egg production systems based on a large data set collected from egg production facilities in Canada. It was found that egg farms are generally operating at high levels of efficiency relative to one another with respect to feed and pullet inputs per tonne of eggs produced both within and between housing system types. DEA results suggest that feed and pullet inputs could decrease across all housing systems between 3.55% and 13.22%, which translated to environmental impacts reductions of up to 17.27%. Least shrinkage and selection operator models were unable to identify key drivers of efficiency for any system except enriched colony housing where an increase in lay cycle length of 1 day was associated with minor increases in efficiency, and the use of brown birds was associated with a 0.95% decrease in efficiency. Further research is necessary to determine key drivers of efficiency that may represent priority strategies for farmers to increase efficiency and decrease environmental impacts. Scenario analyses were used to calculate the cumulative environmental impacts of egg production assuming different distributions of production across housing systems and that DEA-efficient conditions are realized for all farms in each scenario. In all scenarios, 0% of production was attributed to conventional cages, reflecting a complete transition away from conventional production systems over time. The most likely of these scenarios, which included large increases in proportions of enriched and multi-tier free run housing, and moderate increases in free-range and organic housing, exhibited between 90.3% and 100.1% of current (i.e. non DEA-efficient) levels of environmental impacts.