NDF
DIGESTIBILITY AND RUMINAL BYPASS PROTEIN – NIR RUMINAL EQUATION PACKAGE
For Legume-Grass and Legume Hay and Silages
(September 2000)
Legume-grass species are described as,
but not limited to, major legume and grass species, used for forage crops, which
predominate the North Central Region of the United States. Legume, singularly, refers to alfalfa. More specifically, most calibration samples
used in the development of the Licensed Trade Secret were supplied by
commercial testing laboratories in Wisconsin from farms located in the North
Central Region of the United States and generally were not identified by
specific species composition or were identified as alfalfa. Silages, referring to the condition of the
plant material, describe the harvested plant material as being ensiled or
having undergone a fermentation process for preservation. At present, this strictly does not
encompass green cut (fresh) or other plant materials (not described above)
received and processed by Consortium Members for NIR percent rumen undegraded
protein analysis.
Sample Preparation
Sample size – received for analysis by the MEMBER
shall be equivalent to, or greater than, 100 grams of dried ground material.
Sample drying (ONLY FOR SILAGES) – in an oven at 55o
C for up to 48 hours is required.
Microwave drying of samples is unacceptable. It has been demonstrated that oven drying silage samples at 55o
C for 48 hours does not greatly affect CP degradation. The purpose of sample drying is as a
precursor to further sample processing, not a dry matter determination. Samples should be dried to the point that no
appreciable moisture gain or loss occurs during further processing. Weight loss during the drying process is
considered “moisture” and should be accounted for when making any “as received”
analytical determinations.
Sample grinding –
Grind
the entire sample of oven dried plant material through a 2 mm screen in a Wiley
mill. For NIRS analysis, grind the
sample again through a 1mm screen using a cyclone type grinder
NIRS Sample Analysis
NIRS sample
analysis is performed using a NIRSystems model 6500 or 5000 instrument;
compatible Infrasoft International, LLD (ISI) software; and a Consortium
developed or approved instrument standardization file. Mix samples to assure homogeneity prior to
sub-sampling for analysis.
Monitoring and Update
For the first
100 samples received, select 10 samples weighing a minimum of 200 g. Split the 2-mm grind samples into two equal
portions. Store, both the 2 mm Wiley ground and 1mm cyclone ground samples, in
air-tight containers under a temperature and light controlled environment to
preserve sample integrity for a minimum period of two months (sixty days)
following submission of computer files to the Consortium office. Create spectra (NIR) and analysis (ANL)
computer output files to store the spectra and analysis of the 10
selected. Send copies of the computer
files to the Consortium office on the first working day of each month.
The Consortium
may be contacting each MEMBER, within the following sixty days, to submit
additional samples if they are determined to be outlier, unique or otherwise
necessary samples to build the calibration library.
Information may
be sent via electronic mail to Paolo Berzaghi (pberzaghi@facstaff.wisc.edu). Hard copy information and samples should be
mailed to
Paolo Berzaghi
at US Dairy forage Researh Center , Madison, WI 53706, ph: (608) 264-5232.
Variable N Mean SEC RSQ SECV 1-VR #
terms
DNDF30 91 20.10 1.33 0.93 1.58
0.89 136
DNDF48 97 21.68 1.71 0.89 2.01 0.86 136
DNDF3M 89 13.41 1.01 0.86 1.17
0.81 136
RUP 116 21.77 1.18 0.90 1.44 0.86 136
Variable N Mean SEC RSQ SECV 1-VR #
terms
DNDF30 91 20.10 1.33 0.93 1.58
0.89 136
DNDF48 97 21.68 1.71 0.89 2.01 0.86 136
DNDF3M 89 13.41 1.01 0.86 1.17
0.81 136
RUP 102 25.37 1.40 0.95 2.35 0.88 136
DNDF30 Degraded NDF (as % of DM) after 30 hours of in vitro incubation in
rumen fluid (Goering and Van Soest, 1970). The 30
hour time period is most commonly used by labs in the Northeast (Dairy One, Cumberland, FARME Institute,
Miner Institute). In CPM-Dairy, the 30
hour NDF digestibility value is used to adjust fiber digestion rates.
% RUP Percent In situ Rumen Undegraded Protein expressed as a percent of Crude Protein (Hoffman et al, 1999A, Dorshorst and Hoffman, 2000).
Licensed Trade Secret(s) and Documentation is/are considered valid and accurate within these application limitations and are not supported by the Technology’s Creator, WARF or the Consortium for other uses, unless otherwise recommended by the Technology’s Creator or the Consortium based on results following established equation monitoring protocols. It is the responsibility of the MEMBER to determine if use of the Licensed Trade Secret(s) and Documentation falls within the application limitations described as Legume-Grass and Legume Silages and that procedural details are followed. Refer to WARF/NIRS Forage and Feed Testing Consortium Member Trade Secret License Agreement, Appendixes C and D (August