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The genetic basis and dominance relationships of the Naked neck gene and its geographical distribution in local populations is described. The effects on growth, feed efficiency, body composition and meat yield of broilers and the effects on egg laying and egg traits, reproduction and liveability in broiler breeding and laying birds are reviewed. On the whole, the results are encouraging for the future use of these genotypes at high ambient temperatures, either for meat or egg production. The results revealed that the autosomal Naked neck (Na) gene reduces feather mass by about 20% in heterozygous (Ndna) and by about 40% in homozygous (Na/Na) birds. The reduction in feather mass improves heat dissipation through the naked area, leading to a relatively higher tolerance to heat and a higher productivity under high ambient temperatures. It is concluded that heterozygous Naked neck broilers gain about 3 …