Evaluation of wheat-based thin stillage as a water source for growing and finishing beef cattle

Two trials were conducted to evaluate the nutritional value of wheat-based thin stillage as a water source for cattle. In Trial 1, 20 large-framed steers were fed a basal diet based primarily on barley grain and barley silage, with ad libitum access to water or thin stillage at one of three DM concentrations (2, 4, and 6.7%) in a completely randomized design. The trial consisted of a 70-d growing period and a finishing phase. In Trial 2, total-tract nutrient digestibility coefficients of the basal diet and water treatments fed in the growing period were determined in a randomized complete block design using 12 medium-framed steers. The results showed that when only DMI from the basal diet was considered, there was a linear reduction (P<.01) in DMI and a linear improvement (P<.01) in the gain:feed ratio with no effect on daily gain as thin stillage DM concentration increased. No differences were detected in DMI or efficiency of gain when total DMI (basal diet and thin stillage) was considered. Carcass traits indicated a trend toward increased (P<.06) carcass fat with increasing thin stillage DM concentration. Results of Trial 2 indicated a linear improvement (P<.05) in apparent digestibility of DM, CP, NDF, and energy of the total diet (basal diet and thin stillage) as thin stillage DM concentration increased. We concluded that supplementing growing and finishing cattle with thin stillage reduced the amount of the basal diet required for gain and improved nutrient utilization.