Do distillers grains affect beef quality?
US - Recently, Certified Angus Beef commissioned a white paper to evaluate factors affecting beef quality. This study was conducted to review factors that may be involved in a recent decline nationally in beef quality grades.Increased use of corn co-product feeds were mentioned also. An analysis of experiments using distillers grains showed that feeding greater than 30% decreased marbling by about one-third of a marbling score. While the magnitude of the marbling effect of distillers grains feeding on marbling was small, this review set off a fire storm of re-analysis of existing data on the effect of distillers grains on marbling.
Most experiments conducted to date with distillers feeds were designed to measure the nutritional value of the product. So cattle were fed to constant days on feed rather than a constant endpoint. The result is that few individual experiments show negative carcass effects.
To get at the bottom of this issue requires analysis of multiple experiments or studies designed to evaluate carcass effects. Recently, Dr. Allen Trenkle of Iowa State University summarized four ISU studies where cattle were fed up to 40% distillers grains. There was some reduction in marbling at the high levels, but the net value of the carcasses in a typical grid market was not greatly different.
Source: Agriculture Online