Effects of Land Applying Dairy Slurry on the Subsequent Voluntary Intake of Orchardgrass Hays by Growing Dairy Heifers

Many dairy operations have a critical need for available sites to land apply dairy slurry after spring planting, and throughout the summer months. This is especially problematic when dairy producers have large proportions of their acreage planted to corn and alfalfa. One possible way to alleviate this problem is to use perennial grass sods as a summer site for receiving dairy slurry. This approach is attractive because grass sods are harvested as hay or silage numerous times throughout the summer, thereby allowing multiple opportunities for spreading. In addition, the applied nutrients can be utilized by a growing forage crop that does not already fix nitrogen. However, this management strategy is only viable if the voluntary intake of these forages by livestock is not negatively affected. Our objectives were to compare voluntary intakes by growing dairy heifers for orchardgrass hays that were fertilized with either dairy slurry or a commercial N fertilizer (ammonium sulfate) and harvested during late spring (1st cutting) or mid summer (3rd cutting).

Authors: W. K. Coblentz, J. A. Davidson, R. P. Walgenbach, J. L. Posner, and J. L. Hedtcke