Environmental sustainability of soybean–chicken systems: productions, local and global value chains analysis from Paraná and São Paulo states, Brazil

Abstract The global shift towards animal-rich diets has spurred agro-industrial production of soybean and maize feeds, causing significant ecological burdens in Brazil, a major global poultry producer and exporter. Organic soybean-poultry production and the related value chain (VC) have evolved as an alternative to address the sustainability challenges of their conventional counterparts. However, their overall sustainability needs thorough analysis. We studied the environmental sustainability of conventional and organic poultry systems, from production in Brazil to supply to local and global markets, using life cycle assessment. We inventoried and assessed the ecological footprints at all stages of studied VCs: feed production, related poultry production (Chicken eggs and meat), slaughter, and supply to local and global markets. Our findings revealed that, for egg production, both systems had similar feed conversion, with 0.6 kg of soy meal embodied per kg of eggs in conventional eggs and 20% more in organic eggs. Conventional meat production showed 15% better feed efficiency than organic production, with about 0.57 kg of soy meal embodied per kg of both meats’ liveweights. We found several trade-offs among the environmental impacts of the poultry VCs, as impacts fluctuated unpredictably across systems. In eggs’ VCs, compared to the conventional system, the organic system performed significantly better on climate change impacts, ecotoxicity, and biodiversity impacts; had similar energy use as the conventional system, but worse scores on acidification, eutrophication, and particulate matter formation impacts. We found almost similar trends in meat VCs, where organic products had the lowest climate change, ecotoxicity, and biodiversity loss impacts but worse scores in other impact categories. The high impacts across all VCs originated from the burden of intensively produced feeds, the wood used for heating and bedding, manure management, and the extended VCs. Transport footprints of chicken meat from west of Paraná to global markets accounted for up to 30% of the overall products’ carbon footprint, emphasizing the need for improving supply chains’ efficiency, and most importantly, local supply chains, which could also promote locally closed nutrient loops. Sustainability assessments looking additionally at animal welfare, meat quality, and social impacts would improve overall systems appraisal.