|
|
||||||||

* Department of Animal Sciences and
Department of Veterinary Clinical Medicine, University of Illinois, Urbana 61801
Corresponding author:
Jimmy H. Clark; e-mail:
jclark{at}uiuc.edu.
Five multiparous Holstein cows cannulated in the rumen and duodenum that averaged 63 d in milk were used in a 5 x 5 Latin square design with 14-d periods to evaluate the incremental substitution of soyhulls for corn in the diet. Diets contained 23% alfalfa silage, 23% corn silage, and 54% concentrate on a dry matter (DM) basis. Pelleted soyhulls replaced corn in the concentrate to supply 0, 10, 20, 30, or 40% of the dietary DM. The intakes of DM and organic matter were unaffected by treatments. Intakes of acid detergent fiber and neutral detergent fiber increased linearly, but the intake of nonstructural carbohydrates decreased linearly as soyhulls increased from 0 to 40% of dietary DM. The amount of acid detergent fiber and neutral detergent fiber digested was increased whereas the amount of nonstructural carbohydrate digested was decreased in the rumen, in the lower digestive tract, and in the total digestive tract as soyhulls replaced corn in the diet. Passage to the duodenum of nonammonia N, microbial N, nonammonia nonmicrobial N, total essential amino acids, total nonessential amino acids, and total amino acids were not affected by treatments. Yield of milk (29.5 kg/d) was not affected by treatments in this experiment. In a companion experiment, cows fed the 40% SH diet produced 1.2 kg/day per cow less (P < 0.07) milk than cows fed the control diet which is similar to the 1.3 kg/day per cow less milk produced by cows fed the same 40% SH diet in this experiment. Differences in the source of energy (fiber vs. nonstructural carbohydrates), in the amount of fiber and nonstructural carbohydrates digested, and in the site of digestion in the gastrointestinal tract may cause a shortage of the source and/or amount of energy that is required for maximum milk production in high producing cows when more than 30% of the dietary DM that is supplied as corn is replaced with soyhullss.
Key Words: dairy cow nutrient digestion ruminal fermentation soyhull
Abbreviation key: EAA = essential amino acids, MUN = milk urea nitrogen, NANMN = nonammonia nonmicrobial N, NEAA = nonessential amino acids, NFC = nonfiber carbohydrates, SH = soyhulls
This article has been cited by other articles:
![]() |
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] |
||||
![]() |
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] |
||||
![]() |
P. A. Beck, S. Hutchison, C. B. Stewart, J. D. Shockey, and S. A. Gunter Effect of crabgrass (Digitaria ciliaris) hay harvest interval on forage quality and performance of growing calves fed mixed diets J Anim Sci, February 1, 2007; 85(2): 527 - 535. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. R. Ipharraguerre and J. H. Clark Impacts of the Source and Amount of Crude Protein on the Intestinal Supply of Nitrogen Fractions and Performance of Dairy Cows J Dairy Sci, May 1, 2005; 88(e_suppl_1): E22 - E37. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. G. Bateman II, J. H. Clark, and M. R. Murphy Development of a System to Predict Feed Protein Flow to the Small Intestine of Cattle J Dairy Sci, January 1, 2005; 88(1): 282 - 295. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Voelker and M. S. Allen Pelleted Beet Pulp Substituted for High-Moisture Corn: 2. Effects on Digestion and Ruminal Digestion Kinetics in Lactating Dairy Cows J Dairy Sci, November 1, 2003; 86(11): 3553 - 3561. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. R. Ipharraguerre and J. H. Clark Soyhulls as an Alternative Feed for Lactating Dairy Cows: A Review J Dairy Sci, April 1, 2003; 86(4): 1052 - 1073. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |