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15N-Leucine: Health benefits, applications and issues related to ileal endogenous amino acid losses in poultry

Published online by Cambridge University Press:  04 January 2017

R.N. SOOMRO ,
J. YAO ,
M.E. ABD EL-HACK ,
I.H.R ABBASI ,
R. HU ,
M. SAEED ,
M.A. ARAIN ,
S.A. SOOMRO ,
X. YANG  and
J. FOWLER
...Show all authors
R.N. SOOMRO
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China Livestock and Dairy Development Department Quetta, Balochistan 87300, Pakistan
J. YAO*
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
M.E. ABD EL-HACK
Affiliation:
Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
I.H.R ABBASI
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
R. HU
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
M. SAEED
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
M.A. ARAIN
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
S.A. SOOMRO
Affiliation:
Department of Physiology and Biochemistry, Sindh Agriculture University Tando jam 70060, Pakistan
X. YANG
Affiliation:
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
J. FOWLER
Affiliation:
Department of Poultry Science; University of Georgia; Athens, GA 30602, USA
M. ALAGAWANY*
Affiliation:
Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
*
Corresponding authors: [email protected]; [email protected]
Corresponding authors: [email protected]; [email protected]
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Abstract

Having accurate data for ileal amino acid digestibility of a feed ingredient is one of the ways to enhance protein and nitrogen utilisation, improve poultry feeding efficiency, and mitigate ammonia emission and pollution in the environment. Moreover, the precise estimation of endogenous amino acid losses (EAAL) depends on formulating diets on digestible amino acid (DAA) basis. Numerous methods have been reported to determine the endogenous fractions including the regression method, the protein-free diet, and the total digestible nitrogen diet. The EAAL determined by these techniques can help in calculated corrected values for amino acid digestibility, termed true digestibility. Certain dietary components that can be called ‘specific losses’ could lead to higher losses than the basal calculation would indicate. To determine the basal plus specific losses (total endogenous losses), some researchers suggested the 15N-dilution method, which allows the determination of the actual digestibility. This method needs more studies and evaluations because there are some controversial issues about this methodology, such as the validity of the 15N-dilution technique when applied to any amino acid or to total nitrogen, the reference pool for the estimation of the labelling of endogenous fractions/secretions, anti-nutritional agents, the effect of bird age, mucin, different cereal grains, as well as the marker itself and the proper assessment. This review will be focused on the above issues, finding that the recently reported 15N isotopes single injection method could be an easy, time-saving, consistent, and reliable methodology for EAAL estimation in poultry.

Keywords

15N-Leucine single injectionileal (EAAL)digestibilityprocedurefactorspoultry
Type
Reviews
Information
World's Poultry Science Journal , Volume 73 , Issue 1 , March 2017 , pp. 145 - 162
Copyright
Copyright © World's Poultry Science Association 2017 

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