FIFTH AND SIXTH EXONS POLYMORPHISMS OF OVOCALYXIN-32 GENE AND ITS EFFECT ON PRODUCTIVE TRAITS AND EGG QUALITY OF LOCAL IRAQI CHICKENS

Authors

  • Hawraa M.A. Al-Taay Department of Animal Production - College of Agricultural Engineering Sciences, University of Baghdad
  • Bassam G.M. Al-khatib Department of Animal Production - College of Agricultural Engineering Sciences, University of Baghdad

DOI:

https://doi.org/10.36103/8307kw57

Keywords:

age maturity, egg production, local chickens, eggshell

Abstract

This study was conducted to investigate the genotype variations in the ovocalyxin-32 (OCX-32) gene polymorphisms and its effect on productive performance and egg quality traits. A total of 100 prepubertal local hens were used, each housed individually in numbered cages. Blood samples were collected for molecular analysis, starting with DNA extraction, followed by PCR amplification. Subsequently, sequencing analysis was performed. Then the A22385462>G SNP was identified, and it had high significant difference(P≤0.01) in the genotypes distribution percentages. The mutant genotype GG outperformed the AG and AA genotypes, of 45.48%, 42.47%, and 2.4%, respectively. Weekly assessments were conducted to evaluate the influence of this SNP of the different genotypes on productive traits and the results indicated it had high significant differences (P≤0.01) in weekly feed consumption The mutant GG genotype significantly outperformed the AA genotype with (687.57g) in week 11, and superiority in feed consumption (P≤0.05) during weeks 12 (686.68g) and 13 (687.96g), while the hybrid AG genotype surpassed AA genotype with 671.76g in week 13. In the average sexual maturity weight, statistically significant differences (P≤0.05) were observed, though the AG genotype exhibited a higher mean 1438.30 g compared to the AA genotype. This study revealed a significant effects of the A22385462>G SNP polymorphisms on productive performance and no significant differences observed on qualitative traits of egg in the local chickens.

Received: 23/4/2025

Accepted: 13/7/2025

Published: 31/7/2026

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Published

2026-07-31

Issue

Vol. 57 No. 7 (2026)

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Articles

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Copyright (c) 2026 Hawraa M.A. Al-Taay, Bassam G.M. Al-khatib

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How to Cite

Al-Taay, H., & Al-khatib, B. (2026). FIFTH AND SIXTH EXONS POLYMORPHISMS OF OVOCALYXIN-32 GENE AND ITS EFFECT ON PRODUCTIVE TRAITS AND EGG QUALITY OF LOCAL IRAQI CHICKENS. IRAQI JOURNAL OF AGRICULTURAL SCIENCES, 57(7), 1893-1902. https://doi.org/10.36103/8307kw57