Carbon footprint of Creole goat milk production in Peru under crop-residue and Andean shrubland systems

Abstract

CONTEXT: Goat farming in Peru is economically marginal yet essential for rural livelihoods and food security. Creole goats are managed extensively on native rangelands or crop residues, but their greenhouse gas emissions remain poorly quantified. OBJECTIVE: To assess the carbon footprint (CFP) of Creole goat milk production under two contrasting extensive systems in Lima (crop-residue based) and Ancash (shrubland-based), Peru. METHODS: A cradle-to-farm-gate life cycle assessment was conducted on six farms per system during winter and summer. Emissions of CH₄, N₂O and CO₂ were estimated using IPCC methodologies and expressed per kilogram of fat- and protein-corrected milk (FPCM). CFP were analyzed using univariate and mixed-effects models. RESULTS AND CONCLUSIONS: System differences in farm characteristics were more pronounced during summer, when Ancash system, compared to Lima system, showed higher dietary fiber concentrations (42.65% vs 33.10%; p < 0.001) and produced milk with greater total solids content (15.38% vs 13.70%; p < 0.05). However, CFP did not differ significantly between systems, ranging from 0.681 to 1.672 kg CO₂-eq kg⁻¹ FPCM, with enteric fermentation accounting for 74–79% of total emissions. Significant system × season interactions for fuel and electricity emissions revealed contrasting seasonal resource-use responses between systems. These findings indicate that seasonal dynamics are a major driver of emission variability, while overall CFP remained comparable between systems. SIGNIFICANCE: This study provides the first CFP assessment of Creole goat milk production in Peru and highlights the importance of considering ecosystem and seasonal variability when assessing emissions from marginal goat systems.