| Effect of varying total mixed ration particle size on rumen digesta and fecal particle size and digestibility in lactating dairy cows. | |
| | |
MedLine Citation:
|
PMID: 21700040 Owner: NLM Status: In-Data-Review |
Abstract/OtherAbstract:
|
The objective of this experiment was to evaluate the effects of feeding rations of different particle sizes on rumen digesta and fecal matter particle size. Four rumen-cannulated, multiparous, Holstein cows (104±15 d in milk) were randomly assigned to treatments in a 4×4 Latin square design. The diets consisted of 29.4% corn silage, 22.9% ground corn, 17.6% alfalfa haylage, and 11.8% dry grass hay [20% of forage dry matter (DM)] on a DM basis. Dry grass hay was chopped to 4 different lengths to vary the total mixed ration (TMR) particle size. Geometric mean particle sizes of the rations were 4.46, 5.10, 5.32, and 5.84mm for short, medium, long, and extra long diets, respectively. The ration affected rumen digesta particle size for particles ≥3.35mm, and had no effect on distribution of particles <3.35mm. All rumen digesta particle size fractions varied by time after feeding, with soluble particle fractions increasing immediately after feeding and 0.15, 0.6, and 1.18-mm particle size fractions decreasing slightly after feeding. Particle fractions >1.18mmhad ration by time interactions. Fecal neutral detergent fiber (NDF) and indigestible NDF concentrations decreased with increasing TMR particle size. Fecal particle size expressed as total geometric mean particle length followed this same tendency. Fecal particle size, expressed as retained geometric mean particle length, averaged 1.13mm with more than 36% of particles being larger than 1.18mm. All fecal nutrient concentrations measured were significantly affected by time after feeding, with NDF and indigestible NDF increasing after feeding and peaking at about 12h later and then decreasing to preprandial levels. Starch concentrations were determined to have the opposite effect. Additionally, apparent digestibility of diet nutrients was analyzed and DM digestibility tended to decrease with increasing TMR particle size, whereas other nutrient digestibilities were not different among rations. These results show that the critical size for increased resistance to rumen escape is larger than 1.18mm and this critical size is constant throughout the day. This study also concludes that, when using average quality grass hay to provide the range of particle sizes fed, DM digestibility tends to decrease with increasing ration particle size. |
| | |
Authors:
|
D D Maulfair; M Fustini; A J Heinrichs |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: Journal of dairy science Volume: 94 ISSN: 1525-3198 ISO Abbreviation: J. Dairy Sci. Publication Date: 2011 Jul |
Date Detail:
|
Created Date: 2011-06-24 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 2985126R Medline TA: J Dairy Sci Country: United States |
Other Details:
|
Languages: eng Pagination: 3527-36 Citation Subset: IM |
Copyright Information:
|
Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved. |
Affiliation:
|
Department of Dairy and Animal Science, The Pennsylvania State University, University Park 16802, Italy. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: An evaluation of the effect of altering nutrition and nutritional strategies in early lactation on r...
Next Document: Effect of biotin on milk performance of dairy cattle: A meta-analysis.