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Naked neck and frizzle genes for improving chickens raised under high ambient temperature: I. Growth performance and egg production

Published online by Cambridge University Press:  13 December 2013

M.M. FATHI ,
A. GALAL ,
S. EL-SAFTY  and
M. MAHROUS
M.M. FATHI*
Affiliation:
Dept. of Animal Production and Breeding, Qassim University, Buraydah, Saudi Arabia
A. GALAL
Affiliation:
Dept. of Poultry Production, Ain Shams University, Cairo, Egypt
S. EL-SAFTY
Affiliation:
Dept. of Poultry Production, Ain Shams University, Cairo, Egypt
M. MAHROUS
Affiliation:
Dept. of Poultry Production, Ain Shams University, Cairo, Egypt
*
Corresponding author: [email protected]
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Abstract

High ambient temperatures in tropical and subtropical regions adversely affect the growth and egg productive performance of both broiler and laying chickens. Relative humidity and ventilation rate influences bird's performance, particularly when they are reared in open sided poultry houses. Genetic approaches that aid in reducing or altering the extent of plumage cover has, as a result, been adopted in many hot regions. Fortunately, there are some major and marker genes can reduce the deleterious effects of heat stress, naked neck (Na) and frizzle (F) genes being the most notable ones. The bulk of relevant literature has shown that their favourable effects on growth and laying performance are well established. Therefore, the naked neck and frizzle genes can be a viable alternative for broiler and layer production particularly, in the tropical countries where summer temperatures are very high.

Keywords

naked neckfrizzleheat stressgrowthproductive performance
Type
Review Article
Information
World's Poultry Science Journal , Volume 69 , Issue 4 , December 2013 , pp. 813 - 832
Copyright
Copyright © World's Poultry Science Association 2013 

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