Introduction
During recent decades productivity of laying hens increased substantially (Elliot, 2008). Not only egg
number, egg mass, and feed conversion has increased but also persistency of lay has improved. As
such, this must have implications on the optimal amino acid nutrition of current laying hen strains.
Simply stated, increasing egg mass output per hen means an increased amino acid output which has
to be provided by the feed. Moreover, while performance criteria of laying hens have improved, body
weight has decreased (Elliot, 2008). Consequently, the amino acid requirement for maintenance
purposes is influenced. In addition to the quantitative demands for amino acids by the modern laying
hen changing, there also is the potential that the qualitative demands for dietary protein might have
changed as optimum amino acid composition for egg production differs from that for maintenance.
Therefore, the current amino acid recommendations for layers provided by Evonik Degussa Feed
Additives have been revised. Since methionine is considered the first limiting amino acid in most
common diet compositions, literature was screened for methionine response studies in order to derive
a value for optimum dietary methionine level. Subsequently, the optimum amino acid profile was
defined by means of recent ideal protein research which ultimately allowed for calculating optimal
dietary amino acid levels for modern laying hen strains.
Introduction
During recent decades productivity of laying hens increased substantially (Elliot, 2008). Not only egg
number, egg mass, and feed conversion has increased but also persistency of lay has improved. As
such, this must have implications on the optimal amino acid nutrition of current laying hen strains.
Simply stated, increasing egg mass output per hen means an increased amino acid output which has
to be provided by the feed. Moreover, while performance criteria of laying hens have improved, body
weight has decreased (Elliot, 2008). Consequently, the amino acid requirement for maintenance
purposes is influenced. In addition to the quantitative demands for amino acids by the modern laying
hen changing, there also is the potential that the qualitative demands for dietary protein might have
changed as optimum amino acid composition for egg production differs from that for maintenance.
Therefore, the current amino acid recommendations for layers provided by Evonik Degussa Feed
Additives have been revised. Since methionine is considered the first limiting amino acid in most
common diet compositions, literature was screened for methionine response studies in order to derive
a value for optimum dietary methionine level. Subsequently, the optimum amino acid profile was
defined by means of recent ideal protein research which ultimately allowed for calculating optimal
dietary amino acid levels for modern laying hen strains.
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