Date of this Version
Harding, J. L. 2012. Spoilage of wet distillers grains plus solubles when stored in a bunker. MS Thesis. University of Nebraska-Lincoln.
Five studies evaluated the impact of spoilage of wet distillers grains plus solubles (WDGS) on nutrient composition, nutrient losses, and cattle performance. Exp. 1 and Exp. 2 utilized barrels to evaluate the ability of various cover treatments to prevent nutrient changes and losses due to spoilage. In Exp. 3, a 140-d barrel study was conducted to mimic bunker storage under ambient temperature but with no precipitation. Barrels were weighed and sampled on 28 day intervals. In Exp. 4, a 130-d finishing study utilized 60 individually-fed steers fed 3 treatments: a dry-rolled corn based diet (control) and 2 diets containing 40% WDGS replacing DRC. The WDGS was stored in either an uncovered bunker or a silo bag and stored anaerobically. An 84 day growing study utilized 60 individually fed steers in a 2x2 factorial design in Exp. 5. Treatments were bunkered vs. bagged WDGS fed at 15 or 40% of diet DM. Exp. 1 and 2 found that covering wet by-products with plastic resulted in the least nutritional losses and changes. Exp. 3 found that spoilage increased the pH and the amount of OM lost. Calculations suggest 12% of DM was lost during storage in the bunker in Exp. 4. Feeding control, non-spoiled WDGS, or spoiled WDGS did not affect DMI. No differences in ADG, final BW, or G:F were observed between non-spoiled and spoiled WDGS treatments. In Exp. 5, calculations suggest that 6.0% of DM was lost in the bunker. Feeding bunkered WDGS decreased DMI across both levels of dietary WDGS compared to bagged WDGS. The diets containing bunkered WDGS had statistically similar ADG and G:F compared to diets with bagged WDGS.
Advisors: Galen Erickson and Terry Klopfenstein