|
|
||||||||
Department of Animal Science, Michigan State University, East Lansing 48824-1225
The effects of increasing concentrations of dried, pelleted beet pulp substituted for high-moisture corn on digestion and ruminal digestion kinetics were evaluated using eight ruminally and duodenally cannulated multiparous Holstein cows in a duplicated 4 x 4 Latin square design with 21-d periods. Cows were 79 ± 17 (mean ± SD) d in milk at the beginning of the experiment. Experimental diets with 40% forage (corn silage and alfalfa silage) and 60% concentrate contained 0, 6.1, 12.1, or 24.3% beet pulp substituted for high-moisture corn on a dry matter basis. Diet concentrations of neutral detergent fiber (NDF) and starch were 24.3 and 34.6% (0% beet pulp), 26.2 and 30.5% (6% beet pulp), 28.0 and 26.5% (12% beet pulp), and 31.6 and 18.4% (24% beet pulp), respectively. Ruminal dry matter pool decreased and NDF turnover rate increased as dietary beet pulp content increased. Potentially digestible NDF was digested more extensively and at a faster rate in the rumen with increasing beet pulp, resulting in increased total tract NDF digestibility. Passage rates of potentially digestible NDF and of indigestible NDF were not affected by treatment. True ruminal digestibility of starch decreased with increasing beet pulp substitution. This was caused by a linear increase in starch passage rate, possibly because of increasing ruminal fill, and a linear decrease in digestion rate of starch in the rumen, possibly because of reduced amylolytic enzyme activity for lower-starch diets. Although true ruminal starch digestibility decreased when more beet pulp was fed, whole tract starch digestibility was not affected because of compensatory digestion of starch in the intestines. Due to more thorough digestion of fiber in diets containing more beet pulp, whole-tract digestibility of organic matter increased linearly, and intake of digestible organic matter was not affected. Partially replacing high-moisture corn with beet pulp in low-forage diets increased fiber digestibility without reducing whole-tract starch digestibility.
Key Words: beet pulp high-moisture corn site of digestion starch digestion
Abbreviation key: BP = dried, pelleted beet pulp, 0BP = 0% beet pulp treatment, 6BP = 6% beet pulp treatment, 12BP = 12% beet pulp treatment, 24BP = 24% beet pulp treatment, HMC = high-moisture corn, INDF = indigestible NDF, NSC = nonstructural carbohydrate, pdNDF = potentially digestible NDF
This article has been cited by other articles:
![]() |
M. L. Bauer, D. E. Schimek, J. J. Reed, J. S. Caton, P. T. Berg, and G. P. Lardy Influence of pressed beet pulp and concentrated separator by-product on intake, gain, efficiency of gain, and carcass composition of growing and finishing beef steers J Anim Sci, September 1, 2007; 85(9): 2290 - 2297. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Silveira, M. Oba, W. Z. Yang, and K. A. Beauchemin Selection of Barley Grain Affects Ruminal Fermentation, Starch Digestibility, and Productivity of Lactating Dairy Cows J Dairy Sci, June 1, 2007; 90(6): 2860 - 2869. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Seo, C. Lanzas, L. O. Tedeschi, and D. G. Fox Development of a Mechanistic Model to Represent the Dynamics of Liquid Flow Out of the Rumen and to Predict the Rate of Passage of Liquid in Dairy Cattle J Dairy Sci, February 1, 2007; 90(2): 840 - 855. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. R. Ipharraguerre, J. H. Clark, and D. E. Freeman Varying Protein and Starch in the Diet of Dairy Cows. I. Effects on Ruminal Fermentation and Intestinal Supply of Nutrients J Dairy Sci, July 1, 2005; 88(7): 2537 - 2555. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Voelker and M. S. Allen Pelleted Beet Pulp Substituted for High-Moisture Corn: 1. Effects on Feed Intake Chewing Behavior, and Milk Production of Lactating Dairy Cows J Dairy Sci, November 1, 2003; 86(11): 3542 - 3552. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Voelker and M. S. Allen Pelleted Beet Pulp Substituted for High-Moisture Corn: 3. Effects on Ruminal Fermentation, pH, and Microbial Protein Efficiency in Lactating Dairy Cows J Dairy Sci, November 1, 2003; 86(11): 3562 - 3570. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |