Environmental footprint of a byproduct diet including DDGS for swine production in the USA

摘要

Ongoing demand for food, feed, and fuel from corn and soybean raises the price hike and question to environmental sustainability. Byproducts such as distillers dried grain with soluble (DDGS) as an alternative from the supply chain of human food and biofuels were used to formulate swine diets to reduce cost and waste. The objective of this study was to quantify the environmental footprints of alternative byproduct DDGS diets and compare them with a standard corn-soybean meal (SBM) diet. The purpose is to help swine producers to choose an alternative diet that is not only economically but also environmentally benign. Two alternative byproduct diets with low and high DDGS inclusion (10.1% and 28.8% respectively) were formulated using the least cost technique. Inventory for the environmental footprint assessment was from DATA SMART-2017 (SimaPro 8.5.2.0), USDA, and RIA-GREET 2018, as well as literature. The functional unit of the study was a 1 kg diet at farm-gate for the feed production stage. The global warming potential (GWP), land use (LU), water consumption (WC), fossil resources scarcity (FR), and terrestrial ecotoxicity (TE) of the diets were quantified using the ReCiPe 2016 midpoint method (Hierarchist version, SimaPro 8.5.2.0, PRe Consultants), by economic allocation. Environmentalfootprints of the byproduct DDGS diets were lower than the standard Corn-SBM diet by economic allocation. In comparison with the standard corn-SBM diet, a 28.8% DDGS diet, with a displacement ratio of 0.69 betweenDDGS and corn, can save a GWP of about kg CO2 eq. per lb feed at the feed production stage.