used. As can be seen, an entire book could
be written summarizing the results
obtained for feedstuffs alone. The examples
which follow were chosen because, while
demonstrating how NIR can be applied to
the area of feedstuffs, they also demon-
strate many of the important concepts
previously discussed. For the reader who
wishes to know more on a specific deter-
mination, e.g. how well can I expect to
determine NDF in forage samples, there are
several means to get started. The book
by Williams and Norris, Near-Infrared
Technology in the Agricultural and Food
Industries (Williams, 1987), although 10
years old, is excellent, as is the monograph
Analysis of Agricultural and Food Products
by Near Infrared Reflectance Spectroscopy
(Shenk and Westerhaus, 1993). Also, on the
Internet, many companies have web sites
with tutorials and even data sets available,
journals are listing the titles of published
articles and, while there may not be a free
database of NIR articles similar to the
chemometrics database previously listed,
there are many sites with references listed.
As demonstrated in Table 9.2, NIRS has
been used for a wide range of feedstuff200 J.B. Reeves III
Table 9.2.Applications of NIR to animal feedstuffs.
Type of feed Determination(s)
Forages and by-products Dry matter
including those treated Total crude protein (CP), acid detergent fibre-CP, heat-damaged protein
chemically or physically Fibre (neutral and acid detergent, cellulose, hemicelluose, crude fibre,
organic cellular content, total non-structural carbohydrates, etc.)
Digestibility (in situand in vitro, cell wall and dry matter, low and high
digestible fibre fraction)
Lignin (72% H 2 SO 4 KMnO 4 , NaClO 2 , acetyl bromide, etc.)
Lignin composition (nitrobenzene oxidation products)
Energy (net and other measures)
Intake
Alkaloids
Fungal contaminants (chitin and glucosamine)
Dysprosium marker
Minerals (Ca, Cu, Fe, K, Mg, Na, P, S), Si and ash
Botanical composition determinations
Mixed rations and See forage above as appropriate
feed ingredients, Energy (in vitrodigestible, metabolizable, net)
including poultry and Digestible crude protein
swine feeds Lysine in swine feeds
Oil
Starch
Sugars
Sulphur
Silages See forage above as appropriate
Cellulase digestibility
NH 3 , acid detergent- and hot-water insoluble N, insoluble N
pH
True dry matter
Volatile fatty acids
Effect of soil contamination on NIR analysis
Fermentation characteristics
Other materials Any of the above as appropriate
Oesophageal fistula and
faeces samples