widely, from as low as 252 kg CO2-e per tonne for soy meal to as
high as 53,600 kg CO2-e/tonne for ruminant fat. In general, the
production of raw materials is the largest contributor to cradle-to mill
gate emissions, although processing-related emissions are
notable for some inputs such as corn dried distillers grains with
solubles (CDDGS) (Table S4). On average, raw material production
accounts for 72% of emissions for feed inputs delivered to the mill
gate, whereas processing contributes 16% and transportation 12%.
For this reason, sourcing feed materials locally may potentially have
a small influence in reducing supply chain emissions provided the
materials have comparable production-related GHG emissions and
feed conversion efficiencies are similar (Table S4