A feedlot growing and finishing experiment evaluated the effect of including pine-sourced biochar at 0.8 (growing) and 1.0% (finishing) of dietary DM on steer performance, carcass characteristics, and greenhouse gas (GHG) production (Exp 1). Two nutrient mass balance experiments were conducted during winter and summer seasons to evaluate the effect of spreading unprocessed red cedar biochar on the feedlot pen surface on manure nutrient capture and cattle performance (Exp 2). In Exp. 1, the inclusion of biochar in the growing diet did not impact steer performance. The inclusion of biochar in the finishing diet significantly reduced intake and gain, resulting in a lighter and leaner carcass compared to control. Emissions of CH4 and CO2 were not affected by biochar inclusion in the growing or finishing period. In Exp. 2, the winter phase (December to June) evaluated three treatments (5 pens/treatment, 10 steers/pen): biochar spread to pen surface, hydrated lime spread to pen surface, and negative control. There were no differences in nutrient (N and P) intake, calculated nutrient retention, or excretion. Steer performance and carcass traits were not impacted by pen treatment in winter phase. The summer phase (June to November) evaluated biochar spread to pen surface against negative control (5 pens/treatment, 8 steers/pen). There were no differences in N and P intake or calculated excretion, however, calculated nutrient retention was significantly greater for steers on biochar-amended pens. Increased nutrient retention by the animal resulted in increased gain, improved feed efficiency, and a heavier hot carcass weight for steers on biochar treatment. In both winter and summer phases, biochar addition to the feedlot pen surface increased N concentration in manure but did not result in increased kg of N or P removed from feedlot pens due to a lesser quantity of manure removed from biochar-amended pens.
Advisors: Galen E. Erickson & Andrea K. Watso
