title: Distillers By-Product Cattle Diets Enhance Reduced Sulfur Gas Fluxes from Feedlot Soils and Manures.
abstract: Total reduced sulfur (TRS) emissions from animal feeding operations are a concern with increased feeding of high-sulfur distillers by-products. Three feeding trials were conducted to evaluate feeding wet distillers grain plus solubles (WDGS) on TRS fluxes. Fresh manure was collected three times during Feeding Trial 1 from cattle fed 0, 20, 40, and 60% WDGS. Fluxes of TRS from 40 and 60% WDGS manures were 3- to 13-fold greater than the 0 and 20% WDGS manures during the first two periods. In the final period, TRS flux from 60% WDGS was 5- to 22-fold greater than other WDGS manures. During Feeding Trial 2, 0 and 40% WDGS diets on four dates were compared in feedlot-scale pens. On two dates, fluxes from mixed manure and soil near the feed bunk were 3.5-fold greater from 40% WDGS pens. After removing animals, soil TRS flux decreased 82% over 19 d but remained 50% greater in 40% WDGS pens, principally from the wetter pen edges (1.9-fold greater than the drier central mound). During two cycles of cattle production in Feeding Trial 3, TRS soil fluxes were 0.3- to 4-fold greater over six dates for pens feeding WDGS compared with dry-rolled corn diet and principally from wetter pen edges. Soil TRS flux correlated with %WDGS, total N, total P, manure pack temperature, and surface temperature. Consistent results among these three trials indicate that TRS fluxes increase by two- to fivefold when cattle were fed greater levels of WDGS, but specific manure management practices may help control TRS fluxes.
authors.forename: Daniel N
authors.initials: DN
authors.lastname: Miller
authors.forename: Mindy J
authors.initials: MJ
authors.lastname: Spiehs
authors.forename: Vincent H
authors.initials: VH
authors.lastname: Varel
authors.forename: Bryan L
authors.initials: BL
authors.lastname: Woodbury
authors.forename: James E
authors.initials: JE
authors.lastname: Wells
authors.forename: Elaine D
authors.initials: ED
authors.lastname: Berry
mesh_terms: D000821:Animal Feed; D000818:Animals; D002417:Cattle; D004032:Diet; D008372:Manure; D012987:Soil; D013455:Sulfur / Q000032:analysis*; D003313:Zea mays
chemical_list: D008372:Manure; D012987:Soil; D013455:Sulfur