Effect of Feeding Whole Soybeans, Roasted Soybeans, or Distillers Grains in Silage-Based Growing Beef Diets

Summary with Implications An individual feeding experiment was conducted to evaluate the effect of feeding raw whole soybeans (WSB), roasted whole (RSB) soybeans or distillers grains (MDGS) at three inclusions (7%, 14%, or 21% of diet dry matter) on growing performance, compared to a common control diet (0%) with urea. The greater inclusions of roasted soybeans or distillers grains increased gain and efficiency in growing cattle. Cattle fed the 21% inclusion of roasted soybeans were the most efficient, likely due to the protected protein increasing rumen undegradable protein content, and the additional energy from the higher levels of fat and protein. The 21% modified distillers grains diet resulted in the greatest intakes and gain, however efficiency was not improved when compared to the 21% raw whole soybean diet. These data suggest that soybeans can be fed to growing cattle to provide fat and protein, but roasting enhances the response in performance compared to raw soybeans and may be a suitable alternative to distillers grains without impacting performance.