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Measurement of the nutrient value of whole crop wheat and barley silages for ruminants using NIRS - LK0658

Description
The standard technique in the UK for estimating nutrient (e.g. protein, starch etc.) and energy (ME) content of silages is Near Infrared Spectroscopy (NIRS). The method, based on as fed (i.e. wet) silage samples, is fast and cheap, but it relies on two important factors:-

a) the generation of accurate of prediction equations

b) a quality control system to maintain the reliability of the equations between different analytical laboratories.

The formation in 2000 of the Forage Analytical Assurance (FAA) group ensures consistent quality results for grass and maize silage are provided to the UK farmer. The FAA group is a self funded industry body consisting of silage analytical laboratories and accounting for over 95% of UK silage analysis (for the list of companies involved see Appendix).

Unfortunately, there are no agreed NIRS equations for estimating the nutrient and energy values of whole crop wheat and barley silages. Currently individual laboratories use a range of techniques leading to variable and possible inaccurate values being supplied.


The standard UK method for estimating ME uses sheep to generate dry organic matter digestibility (DOMD - also known as D value), which is multiplied by a conversion factor to give the ME. The correct conversion factor from DOMD to ME for whole crop wheat and barley silage is not known, and nutritionists currently use the maize silage value.

Commercially and environmentally it is essential that the farmer or farm advisor has accurate and reliable analysis of the crop on each individually farm. Incorrect analysis will not only reduce animal performance and health, but will lead to incorrect and wasteful use of nutrients such as nitrogen.


Objective

a) To develop and implement reliable wet NIRS equations to predict standard nutrients (e.g. dry matter, crude protein, starch, pH etc.).

b) To develop and implement reliable wet NIRS equations to predict silage organic matter digestibility (DOMD) for ruminants.

c) To measure and implement the appropriate conversion factor from DOMD to ruminant Metabolisable Energy (ME).
Project Documents
• Abstract : Measurement of the nutrient value of whole crop wheat and barley silages for ruminants using NIRS   (3698k)
• Executive Summary : Measurement of the nutrient value of whole crop wheat and barley silages for ruminants using NIRS   (3694k)
Time-Scale and Cost
From: 2003

To: 2005

Cost: £61,824
Contractor / Funded Organisations
Biotal Limited, Milk Development Council, Alltech UK, Forage Analytical Assurance Group, Trouw UK) Ltd, Maize Growers Association, University - Reading, National Institute of Agricultural Botany, Volac International Ltd, ABN Ltd
Keywords
Analytical Chemistry              
Cattle              
Dairy              
Farming              
Livestock Farming              
Nutrition              
Sheep              
Sustainable Farming and Food