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Identifying variation in the nutritional value of corn based on chemical kernel characteristics

Published online by Cambridge University Press:  28 June 2013

C.K. GEHRING
Affiliation:
Department of Poultry Science, Auburn University, AL 36849, USA
A.J. COWIESON
Affiliation:
Poultry Research Foundation, The Faculty of Veterinary Science, University of Sydney, Camden, NSW 2570, Australia
M.R. BEDFORD
Affiliation:
AB Vista Feed Ingredients, Marlborough, Wiltshire, SN8 4AN, United Kingdom
W.A. DOZIER III*
Affiliation:
Department of Poultry Science, Auburn University, AL 36849, USA
*
Corresponding author: [email protected]
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Abstract

The metabolisable energy of corn can vary by more than 400 kcal/kg in poultry. Chemical, rather than physical kernel characteristics may be more accurate for predicting nutrient and energy availability. Factors that affect variability include genetics, agronomic conditions, proximate composition, pre- and post-harvest processing variables, and the presence of anti-nutritional factors. Variation in the nutritional value of corn may be better identified when the relationship between protein and starch are considered rather than by total content or predicted digestibility values alone. Recently, the use of near-infrared reflectance spectroscopy has made rapid valuation of corn based on chemical kernel characteristics a possibility. Prediction equations may be useful for formulating diets to more closely approximate actual metabolisable energy content for poultry.

Type
Review Article
Copyright
Copyright © World's Poultry Science Association 2013

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