Date of this Version
Jolly, M. L. 2013. Evaluation of oil extraction on corn dry-milling byproducts in growing and finishing cattle diets. M.S. Thesis. University of Nebraska.
Dry-milling ethanol plants produce distillers grains (DG) and condensed distillers solubles (CDS). Before thin stillage is evaporated to CDS, corn oil is removed via centrifugation, producing de-oiled CDS. Depending on plant availability, CDS can be marketed or combined with DG to produce de-oiled distillers grains plus solubles (DGS). Currently, there are no data available on animal performance when corn oil is removed via centrifugation of the solubles stream. Therefore, two finishing experiments, a metabolism experiment, and a growing experiment were conducted to evaluate the effects of corn oil removal on cattle performance, carcass characteristics, and the effects on nutrient digestibility. Oil concentration had no effect on DMI, ADG, G:F, and carcass characteristics in finishing cattle fed de-oiled or normal DGS or CDS. Regardless of oil concentration, steers fed DGS or CDS had greater ADG and were more efficient than the corn-based control. Diets containing normal CDS had greater fat digestibility compared to de-oiled CDS, while there was no difference for DGS. The growing experiment suggested that there were no differences in ending BW, DMI, or ADG for the main effects of oil concentration. At lower concentration of dietary CDS, G:F improved 13.6% for normal CDS compared to de-oiled CDS. However, when CDS increased to 40% inclusion, G:F differed by only 1% which could be a result of hindered fiber digestion for normal CDS. In finishing diets, oil removal via centrifugation had no effect on animal performance or carcass characteristics. However, in growing trials, normal CDS fed at low inclusions resulted in improved G:F compared to de-oiled CDS with no difference observed at greater inclusions.
Advisors: Galen E. Erickson and Terry J. Klopfenstein