International Journal of Molecular Zoology, 2024, Vol.14, No.6, 334-343 http://animalscipublisher.com/index.php/ijmz 338 5 Case Study: Successful Implementation of Genomic Selection in Poultry Breeding 5.1 Background and context of the breeding program The implementation of genomic selection in poultry breeding has been driven by the need to enhance genetic progress and improve economically important traits. Traditional genetic improvement programs in poultry already benefit from short generation intervals, with broilers selected every six weeks and layers on an annual basis (Wolc et al., 2016). However, genomic selection offers the potential to further accelerate genetic gains by utilizing high-density SNP panels to predict breeding values more accurately and efficiently (Misztal et al., 2020). 5.2 Genomic data collection and evaluation The methodology for implementing genomic selection in poultry involves several key steps. First, genomic data is collected using high-density SNP panels, which provide comprehensive coverage of the chicken genome (Figure 2) (Wolc et al., 2016; Li et al., 2017). For instance, in a study involving 78 chickens from 14 populations, whole-genome sequencing was performed to identify approximately 6.44 million SNPs per population. This data is then combined with phenotypic information to create genomic relationship matrices, which are used to estimate breeding values through models such as the single-step genomic BLUP (ssGBLUP) (Misztal et al., 2020). This approach integrates genomic and pedigree information, ensuring accurate and unbiased predictions of breeding values. Figure 2 Sample information and comparison of identified SNPs in each breed/population with the chicken variants database (dbSNP, Build 145) (Adopted from Li et al., 2017) Image caption: Known SNPs are SNPs already in chicken dbSNP. The map displayed here is the geographic distribution of domestic chicken populations; numbers above the dashed lines are altitudes. Red and green localities represent eight lowland and six highland chicken populations respectively, sampled in this study (Adopted from Li et al., 2017) 5.3 Improvements in targeted traits The implementation of genomic selection in poultry breeding has led to significant improvements in various targeted traits. For example, in a study on indigenous chicken breeding programs, the use of genomic selection resulted in a 59.3% increase in genetic gain and a 30% improvement in selection accuracy compared to conventional breeding schemes (Ndung’u et al., 2022). Additionally, genomic selection has been shown to enhance traits such as body weight, egg production, and feed efficiency in different chicken breeds (Abdelmanova
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