|POWELL, J MARK|
|Ehlke, N - U OF MINNESOTA|
Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: April 14, 2004
Publication Date: August 23, 2004
Citation: Grabber, J.H., Broderick, G.A., Sullivan, M.L., Hatfield, R.D., Powell, J.M., Rotz, C.A., Muck, R.E., Ehlke, N.J. 2004. Protein-binding polyphenols enhance nitrogen cycling and profitability of dairy farms. In: 228th ACS National Meeting, August 22-26, 2004, Philadelphia, Pennsylvania. 2004 CDROM. Technical Abstract: We are conducting systems research to characterize how condensed tannins and other forage polyphenols influence protein utilization by dairy cattle, nitrogen loss and cycling in manure and crop systems, and farm profitability. Polyphenol-containing forages undergo less proteolysis during ensiling and ruminal fermentation, providing up to 50% more forage protein for gastrointestinal digestion and absorption by cattle. In feeding trials, forages with polyphenols increased N-use efficiency or milk yields up to 15% and decreased labile nitrogen excretion in manure up to 15%. Field and laboratory trials will reveal how polyphenols influence nitrogen loss and cycling during manure handling and crop production. Preliminary farm-level simulations indicate that the use of a polyphenol-containing alfalfa on dairy farms would increase long-term farm profitability up to 12% and reduce nitrogen losses up to 25%. Because of the potential economic and environmental benefits, we are partnering with other groups to develop alfalfa with optimal polyphenol concentrations.