Feed conversion ratio (FCR) is one of the most economically significant traits in poultry production, as it directly affects feed costs, production efficiency, environmental sustainability, and overall profitability. Improving feed efficiency has become a major objective of poultry breeding programs due to the increasing global demand for animal protein and the rising cost of feed ingredients. While conventional selection methods have achieved considerable genetic progress, recent advances in molecular genetics and functional genomics have accelerated the identification of molecular biomarkers associated with feed efficiency. These biomarkers provide valuable insights into the biological mechanisms regulating nutrient utilization and offer powerful tools for precision breeding and nutritional management.
Recent developments in high-throughput sequencing technologies, genome-wide association studies (GWAS), transcriptomics, proteomics, metabolomics, epigenomics, and microbiome profiling have enabled the discovery of numerous biomarkers linked to feed conversion ratio. Candidate genes involved in energy metabolism, mitochondrial function, muscle growth, lipid metabolism, appetite regulation, immune responses, oxidative stress, and intestinal integrity have been identified as key regulators of feed efficiency. Furthermore, circulating microRNAs, DNA methylation patterns, protein expression profiles, and metabolite signatures have emerged as promising biomarkers for predicting feed utilization and production performance in commercial poultry populations.
The integration of molecular biomarkers into genomic selection programs has significantly improved the accuracy of breeding value estimation for feed efficiency traits. Combined with artificial intelligence, machine learning, and precision livestock farming technologies, biomarker-based prediction models enable early identification of genetically superior birds, reducing the need for extensive phenotypic measurements and lowering breeding costs. In addition, molecular biomarkers facilitate the development of precision nutrition strategies by identifying biological pathways that respond to dietary interventions, thereby improving nutrient digestibility, gut health, immune competence, and metabolic efficiency.
Despite these remarkable advances, several challenges continue to limit the routine application of molecular biomarkers in commercial poultry production. These include insufficient validation across diverse genetic populations, environmental influences on biomarker expression, high analytical costs, data integration complexity, and the need for standardized protocols. Future research should focus on integrating multi-omics technologies, functional genomics, nutrigenomics, microbiome analysis, and advanced computational approaches to validate robust biomarkers suitable for large-scale breeding programs. Overall, molecular biomarkers represent a promising frontier in poultry science, offering new opportunities to improve feed conversion ratio, accelerate genetic progress, enhance production sustainability, and support evidence-based precision breeding strategies for the future poultry industry.