Farmers prefer to grow some high-tannin sorghum varieties because birds don’t eat as much of the grain, but what about cattle? In research reported in the Journal of Animal Science, University of Wisconsin researchers compared high-tannin sorghum, corn or a one-to-one mixture of the two grains for finishing Angus-cross steers. Each ration contained about 75 percent grain. Feeding high-tannin sorghum compared to corn resulted in lower average daily gains and lighter final weights but higher feed efficiency. The mixed diet resulted in about the same gains and final weights as corn, along with higher feed efficiency than the average of high-tannin sorghum and corn, indicating a positive combination effect.
Compared to corn, steers on the high-tannin sorghum diet had less carcass fat cover and superior yield grades but, because of lighter carcass weight, had fewer total pounds of retail product. The mixed diet was intermediate in fat and yield grade. The researchers found no differences in mechanical tenderness in beef from the three groups, but taste panelists rated samples from the high-tannin sorghum group as less tender and less juicy beef compared to the corn-fed group. Beef from the mixed ration tended to have slightly higher taste-panel tenderness. The authors concluded that the mixed ration compares favorably with corn for performance and carcass quality.