Gene Frequency of Plumage Pattern, Comb Type, Skin Colour, and Feather Traits in Indigenous Chickens of Kerala, India

Abstract

Indigenous chickens in India represent a vital genetic resource due to their adaptability, phenotypic diversity, and contribution to rural livelihoods. This study aimed to evaluate the phenotypic distribution and allelic frequency of major genes affecting qualitative traits in indigenous chicken populations from two districts in Kerala. A total of 200 adult birds from Kozhikode and Kannur were assessed for plumage pattern, comb type, skin colour, and feather traits, including frizzling, naked neck, ptilopody, and crest. Phenotypic frequencies and corresponding allele distributions were calculated and tested against the hypothesis of dominant and recessive alleles were at equal frequency (p = q = 0.50). Results revealed considerable plumage variability, with multicolour types predominating, likely reflecting both cultural preferences and adaptive advantages. Traits governed by autosomal incompletely dominant genes such as pea comb, naked neck, frizzling, ptilopody, and crest were observed at low frequencies. Dominant alleles for frizzling (F = 0.005), naked neck (Na = 0.005), ptilopody (Pti = 0.008) and crest (Cr = 0.01) exhibited significant (P < 0.001) deviation from expected ratios, suggesting strong negative selection. Skin colour variation revealed a higher frequency of the recessive yellow allele (w = 0.60), consistent with ancestral hybridization between red and grey junglefowl. These findings indicate an ongoing loss of adaptive and aesthetic traits in indigenous chickens, underscoring the need for targeted conservation strategies to preserve their unique genetic heritage.