Early weaning of calves and its impact on the greenhouse gas emissions intensity of a complete beef cattle operation from the Humid Pampas of Argentina

Grass-based beef cattle systems have limited opportunities to adopt novel input-based greenhouse gas (GHG) mitigation options. Furthermore, these systems are highly susceptible to extreme weather events, triggering large fluctuations in the quality and quantity of forage supplies. Early weaning is a common management practice used in grazing beef cattle systems, a climate change adaptation measure to reduce economic and productivity risks. However, there is little information regarding its impact on GHG emissions intensity at the farm level in complete beef cattle operations. This study aimed to compare early vs. traditional weaning on GHG emissions intensity of a complete beef cattle operation from the southeastern Pampas region of Argentina. The total GHG emissions, productivity, and GHG emissions intensity were estimated based on IPCC Tier 2, considering on-farm and off-farm GHG embedded emissions of inputs. Two production systems with alternative weaning management (early vs. traditional) were modeled based on observed animal performance under actual field conditions along with data from the literature. Early weaning reduced total GHG emissions by 10%, beef production by 3%, and GHG emissions intensity of the production system by 8%. Results suggest that early weaning, a useful management practice during extreme weather events, can reduce GHG emissions in grass-based beef production systems.