Document Detail


Using the Small Ruminant Nutrition System to develop and evaluate an alternative approach to estimating the dry matter intake of goats when accounting for ruminal fiber stratification.
MedLine Citation:
PMID:  25200784     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
The first objective of this research was to assess the ability of the Small Ruminant Nutrition System (SRNS) mechanistic model to predict metabolizable energy intake (MEI) and milk yield (MY) when using a heterogeneous fiber pool scenario (GnG1), compared with a traditional, homogeneous scenario (G1). The second objective was to evaluate an alternative approach to estimating the dry matter intake (DMI) of goats to be used in the SRNS model. The GnG1 scenario considers an age-dependent fractional transference rate for fiber particles from the first ruminal fiber pool (raft) to an escapable pool (λr), and that this second ruminal fiber pool (i.e., escapable pool) follows an age-independent fractional escape rate for fiber particles (ke). Scenario G1 adopted only a single fractional passage rate (kp). All parameters were estimated individually by using equations published in the literature, except for 2 passage rate equations in the G1 scenario: 1 developed with sheep data (G1-S) and another developed with goat data (G1-G). The alternative approach to estimating DMI was based on an optimization process using a series of dietary constraints. The DMI, MEI, and MY estimated for the GnG1 and G1 scenarios were compared with the results of an independent dataset (n = 327) that contained information regarding DMI, MEI, MY, and milk and dietary compositions. The evaluation of the scenarios was performed using the coefficient of determination (R(2)) between the observed and predicted values, mean bias (MB), bias correction factor (Cb), and concordance correlation coefficient. The MEI estimated by the GnG1 scenario yielded precise and accurate values (R(2) = 0·82; MB = 0.21 Mcal/d; Cb = 0.98) similar to those of the G1-S (R(2) = 0.85; MB = 0.10 Mcal/d; Cb = 0.99) and G1-G (R(2) = 0.84; MB = 0.18 Mcal/d; Cb = 0.98) scenarios. The results were also similar for the MY, but a substantial MB was found as follows: GnG1 (R(2) = 0.74; MB = 0.70 kg/d; Cb = 0.79), G1-S (R(2) = 0.71; MB = 0.58 kg/d(1); Cb = 0.85) and G1-G (R(2) = 0.71; MB = 0.65 kg/d; Cb = 0.82). The alternative approach for DMI prediction provided better results with the G1-G scenario (R(2) = 0.88; MB = -71.67 g/d; Cb = 0.98). We concluded that the GnG1 scenario is valid within mechanistic models such as the SRNS and that the alternative approach for estimating DMI is reasonable and can be used in diet formulations for goats.
Authors:
J G L Regadas Filho; L O Tedeschi; A Cannas; R A M Vieira; M T Rodrigues
Related Documents :
25235834 - Multichannel myopic deconvolution using ambient noise sources.
9631294 - The use of solid physical models for the study of macromolecular assembly.
20333124 - 5-cm(-1) band model option to lowtran5.
25444744 - A mathematical procedure to estimate the impact of a change in method on discordance or...
19181314 - Temporal trends in bull semen quality: a comparative model for human health?
11275334 - Development and implementation of the population fisher information matrix for the eval...
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2014-9-5
Journal Detail:
Title:  Journal of dairy science     Volume:  -     ISSN:  1525-3198     ISO Abbreviation:  J. Dairy Sci.     Publication Date:  2014 Sep 
Date Detail:
Created Date:  2014-9-9     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  2985126R     Medline TA:  J Dairy Sci     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
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:  Short communication: Amino trap column improving the separation of methylimidazoles, 5-hydroxymethyl...
Next Document:  Feeding lactating dairy cattle long hay separate from the total mixed ration can maintain dry matter...