|Jung, Hans Joachim|
|Lauer, Joe -|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: August 20, 2011
Publication Date: September 20, 2011
Citation: Jung, H.G., Lauer, J. 2011. Corn silage fiber digestibility: key points, historical trends, and future opportunities. In: 72nd Minnesota Nutrition Conference Proceedings, September 20-21, 2011, Owatonna, Minnesota. p. 30-44. Technical Abstract: Digestibility of corn silage fiber is being increasingly emphasized in hybrid selection for dairy cow feeding. While extent to which fiber is digested is clearly related to lignin content of the silage, prediction of fiber digestion from simple measurements of lignin concentration is unreliable. This dichotomy between biological mechanism and prediction ability arises from the complexity of corn plant tissue and cellular anatomy, and cell wall chemistry. A review of the last 20 years of annual corn hybrid trials in Wisconsin indicates a possible change in silage fiber digestibility among commercially available hybrids, but a controlled era of variety release study did not detect any alterations before the year 2000. In The Netherlands corn hybrids actually suffered declines in fiber digestion potential from 1975 to 1985 but then increased until 2000 when progress appears to have reached a plateau. The lack of sustained progress in fiber digestibility improvement is likely due to limited commercial breeding effort because fiber digestion is highly heritable. However, the brown midrib mutation and other genetic modifications to cell wall structure that improve fiber digestibility and cow performance are being identified. Hopefully these advances will be incorporated into future commercial corn hybrids.