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The gizzard: function, influence of diet structure and effects on nutrient availability

Published online by Cambridge University Press:  20 June 2011

B. SVIHUS*
Affiliation:
Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, PO Box 5003, N-1432 Aas, Norway
*
Corresponding author: [email protected]
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Abstract

The gizzard has a number of important functions, such as aiding digestion by particle size reduction, chemical degradation of nutrients and regulation of feed flow, and responds rapidly to changes in the coarseness of the diet. This review summarises findings on the function of the gizzard, the interaction between diet and gizzard function, and the nutritional consequences of these interactions. Due to the reported improvements in nutrient availability when structural components which stimulate gizzard development has been added to the diet, it may be recommended to include at least 20 to 30% cereal particles larger than 1 mm in size, or to include at least 3% coarse fibres such as oat hulls, in the diet.

Type
Review Article
Copyright
Copyright © World's Poultry Science Association 2011

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