New Concepts in Nutritional Management of Dry Cows James K. Drackley and Heather M. Dann Department of Animal Sciences, University of Illinois, Urbana, Illinois 61822 email: drackley@uiuc.edu Take home messages • Low-energy diets during the early (far-off) dry period show promise in decreasing health problems in fresh cows, and may be more important than typical close-up diets. • Addition of chopped straw to a TMR is a popular method to decrease ration energy density while allowing cows to eat all they want. • Several factors may impact the success of this approach, and those factors are summarized in this article. Introduction Dry cow nutrition has been an active area of research over the last half-century. In particular, the last two decades have seen intensive interest in management of cows during the so-called “close-up” or “transition” period, generally considered to be about the last 21 days before calving through 21 days after calving (Grummer, 1995). The intense research effort has resulted in better understanding of the biology of cows during this turbulent period, and some insight into how to feed cows during the close-up dry period. However, the lack of repeatable success with close-up dry period nutrition programs in decreasing the occurrence of health disorders and increasing subsequent milk production has been frustrating and problematic to farmers, nutritionists, and researchers (Drackley, 1999). It has been said that “there is very little new under the sun”. Indeed, many ideas and practices cycle in and out of popularity, with new applications or new subtleties. The “new concepts” to be discussed in this paper fall into that category. Interest in low energy, high forage diets for cows during the dry period has been renewed in the last two to three years. Systems being implemented include high-straw, one-group total-mixed rations (TMR) for the entire dry period; lower inclusion rates of straw with other forages in one- or two-group systems; use of high-fiber by-product feeds to lower starch content; and a variety of other combinations and modifications. Our research group is extremely interested in the potential of these approaches to decrease calving-related health problems. Field application and testing of 1