Genomic selection in livestock breeding programs:A systematic literature review

Abstract

Genomic selection (GS) has radically changed the breeding practice of livestock as it allows the prediction of the genomic estimated breeding values (GEBVs) with dense genome-wide single nucleotide polymorphism (SNP) markers. This is a systematic literature review that incorporates the empirical evidence that was published in 2001-2024 to assess the use, validity, and effectiveness of genomic selection in large livestock species, such as dairy cattle, beef cattle, pigs, poultry, and small ruminants. In accordance with the PRISMA guidelines, 128 peer-reviewed articles were part of the qualitative synthesis, and 96 of them included quantitative data to be compared. Findings indicate that genomic selection is always able to enhance the ability to predict, especially the dairy cattle production traits (0.65-0.75), as well as availability to increase selection efficiency in low-heritability reproductive and health traits in all species. Declines in generation interval, especially in dairy cattle, decreasing to 2-2.5 years in place of the previous 5-6 years, appeared as the major source of higher genetic gain annually, and the improvements were 25-100% relative to the conventional pedigree-based selection systems. Recent methodology, especially the use of single-step genomic best linear unbiased prediction (ssGBLUP) instead of multi-step methods and the Algorithm for Proven and Young (APY) has enhanced the performance and enabled large-scale application. In spite of the difficulties connected with the size of reference population, breed diversity, and genetic control in the case of inbreeding, genomic selection has shown to have a stable economic and genetic benefit in all the livestock sectors. In general, this review demonstrates that genomic selection is a powerful, scalable, and economically feasible approach to genetic enhancement of livestock production systems in the world.