Integration of Metabolomics and Transcriptomics to Improve Feed Utilization Efficiency in Meat-Type Chickens

Feed constitute 65% of total production costs. Feed nitrogen (N) and phosphorus (P) utilizations are 30-50% in poultry. Unutilized N and P in excreta when applied in excess to land cause environmental pollution. Increased utilizations of N and P and improvements in feed efficiency (FE) will improve production performance. The major challenges to improving the genetics of feed efficiency in poultry are defining feed efficiency phenotypes and development of functional genetic markers for selection of birds. We have examined the nutritional phenotypes, duodenal transcriptomics and plasma metabolites in divergently selected broiler chickens (high vs. low feed efficiency lines). Our analysis indicated that improved FE is associated with high N, calcium and low fat retentions. The transcriptomic data suggested that improved FE is associated with high cell growth and proliferation, and less apotosis, upregulation of glycolysis, efficient N digestion and retention, and renal function for N recycling. The metabolomic analysis also showed the strong association between plasma glutamate and N recycling. The metabolomic data reveals the posttranscriptional and posttranslational mechanisms associated with transcriptomics, and therefore can directly link feed efficiency phenotypes to their respective genotypes.