Effects of Grain Variability and Processing on Starch Utilization by Lactating Cows

One of the fundamental principles of dairy nutrition is the need to formulate rations to maximize energy intake for high producing cows. We have improved our ability to predict dry matter intake (DMI) and can formulate rations for increasingly precise fractions of carbohydrate, but a major limitation to the science of carbohydrate allocation continues to be the unaccounted variability in starch digestibility in the rumen and total tract among grains and the resulting effects on milk production. My objectives are to help identify sources of this variability and some concepts to help nutritional advisors make ration decisions with less trial feeding to groups of cows. Benefits of reduced variability are hard to measure in the short run, but probably decrease feed costs and increase cow longevity through a more sustainable feeding regimen.