THIN STILLAGE FROM WHEAT-BASED ETHANOL-PRODUCTION AS A NUTRIENT SUPPLEMENT FOR CATTLE GRAZING CRESTED WHEATGRASS PASTURES

An 84-d trial was conducted to evaluate the use of thin stillage from wheat based ethanol production as a nutrient supplement for cattle gra zing crested wheatgrass. Forty medium-frame steers were allotted to ei ght CWG pastures (5 pasture(-1)) and supplied with either water or thi n stillage as a fluid source. Measurements included daily intake of fl uid, biweekly weight gains, start and end of test ultrasonic backfat m easurements, and blood plasma samples on days 42, 56, and 70 of the tr ial. Samples of thin stillage and biweekly clippings of the CWG pastur es were collected throughout the trial for analysis. Thin stillage ave raged 8.4 +/- 0.35, 48.5 +/- 1.83, 9.6 +/- 1.63, 34.5 +/- 4.55, and 3. 4 +/- 0.44% (DM basis) CP, EE, NDF and ADF, respectively. Cattle with access to thin stillage exhibited superior (P < 0.05) weight gains fro m day 42 through day 84 of the trial. Cumulative weight gains were 1.3 9 +/- 0.14 and 0.91 +/- 0.27 kg d(-1), respectively, for the thin stil lage and water fed cattle (P < 0.05), an increase of 53%. Fluid intake of the cattle on stillage was 48.2 +/- 2.7 L d(-1) or 67% greater (P < 0.05) than that for animals on water (28.9 +/- 1.53 L d(-1)). Daily DM intake from thin stillage estimated from fluid intake was 4.1 kg. T he superior liveweight gain of cattle fed thin stillage was reflected in higher (P < 0.05) backfat levels at the end of test (2.51 vs. 0.6 m m) and higher (P < 0.05) plasma urea, Mg, and P levels. The results of this study indicate that thin stillage from wheat-based ethanol produ ction is a valuable nutrient source for cattle grazing CWG.