HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Corona, L. Articles by Zinn, R. A. Search for Related Content PubMed PubMed Citation Articles by Corona, L. Articles by Zinn, R. A.

Impact of corn vitreousness and processing on site and extent of digestion by feedlot cattle

Department of Animal Science, University of California, Davis

³ Corresponding author: razinn{at}ucdavis.edu

Eight cannulated Holstein steers (average BW: 251 kg) were used in 2 simultaneous 4 x 4 Latin squares in a split-plot arrangement to test the effects of processing method [dry-rolled (DR) vs. steam-flaked (SF); main plot] and vitreousness (V, %; subplot) of yellow dent corn (V55, V61, V63, and V65) on site of digestion of diets containing 73.2% corn grain. No vitreousness x processing method interactions were detected for ruminal digestion, but ruminal starch digestion was 14.4% lower (P < 0.01) for DR than for SF corn. Interactions were detected between vitreousness and processing method for postruminal (P < 0.10) and total tract digestion (P < 0.05). With DR, vitreousness tended to decrease (linear effect, P < 0.10) postruminal OM and starch digestion. With SF, vitreousness did not affect (P 0.15) postruminal digestion of OM and starch. Postruminal N digestion tended to decrease (linear effect, P = 0.12) as vitreousness increased. Postruminal digestion was greater for SF than for DR corn OM (25.7%, P < 0.05), starch (94.3%, P < 0.10), and N (10.7%, P < 0.01). Steam flaking increased total tract digestion of OM (11%, P < 0.05), starch (16%, P < 0.01), and N (8.4%, P < 0.05) but decreased total tract ADF digestion (26.7%, P < 0.01). With DR, total tract starch digestion was lower for V65 (cubic effect, P < 0.10) than for the other hybrids. With SF, total tract starch digestion was not affected (P 0.15) by vitreousness. Fecal starch and total tract starch digestion were inversely related (starch digestion, % = 101 – 0.65 x fecal starch, %; r² = 0.94, P < 0.01). Ruminal pH was greater for steers fed DR than for steers fed SF corn (6.03 vs. 5.62, P < 0.05). Steam flaking decreased (P < 0.01) the ruminal molar proportion of acetate (24%), acetate:propionate molar ratio (55%), estimated methane production (37.5%), and butyrate (11.3%, P < 0.05). There was a vitreousness x processing interaction (P < 0.01) for acetate:propionate. For DR, acetate:propionate tended to increase (linear effect; P < 0.10) with increasing vitreousness. With SF, acetate:propionate was greater (cubic effect, P < 0.01) for V65. Starch from more vitreous corn grain was less digested when corn grain was DR, but this adverse effect of vitreousness on digestion was negated when the corn grain was SF. Of the 19% advantage in energetic efficiency associated with flaked over rolled corn grain, about can be attributed to increased OM digestibility, with the remaining ascribed to reduced methane loss.

Key Words: corn • cattle • digestion • processing • vitreousness

This article has been cited by other articles:

				F. W. Harrelson, M. K. Luebbe, N. F. Meyer, G. E. Erickson, T. J. Klopfenstein, D. S. Jackson, and W. A. Fithian Influence of corn hybrid and processing method on nutrient digestibility, finishing performance, and carcass characteristics J Anim Sci, July 1, 2009; 87(7): 2323 - 2332. [Abstract] [Full Text] [PDF]

				B. E. Depenbusch, E. R. Loe, M. J. Quinn, M. E. Corrigan, M. L. Gibson, K. K. Karges, and J. S. Drouillard Corn distillers grains with solubles derived from a traditional or partial fractionation process: Growth performance and carcass characteristics of finishing feedlot heifers J Anim Sci, September 1, 2008; 86(9): 2338 - 2343. [Abstract] [Full Text] [PDF]

				B. E. Depenbusch, J. S. Drouillard, E. R. Loe, J. J. Higgins, M. E. Corrigan, and M. J. Quinn Efficacy of monensin and tylosin in finishing diets based on steam-flaked corn with and without corn wet distillers grains with solubles J Anim Sci, September 1, 2008; 86(9): 2270 - 2276. [Abstract] [Full Text] [PDF]

				B. E. Depenbusch, T. G. Nagaraja, J. M. Sargeant, J. S. Drouillard, E. R. Loe, and M. E. Corrigan Influence of processed grains on fecal pH, starch concentration, and shedding of Escherichia coli O157 in feedlot cattle J Anim Sci, March 1, 2008; 86(3): 632 - 639. [Abstract] [Full Text] [PDF]

				J. C. Marini, D. G. Fox, and M. R. Murphy Nitrogen transactions along the gastrointestinal tract of cattle: A meta-analytical approach J Anim Sci, March 1, 2008; 86(3): 660 - 679. [Abstract] [Full Text] [PDF]