Multi-omics profiling of hepatic macromolecules in laying hens with difference feed intake: Mechanistic insights into antioxidant capacity modulation.

Currently, the cost of poultry feed accounts for more than 70 % of the total cost of poultry production. Therefore, it is crucial to find appropriate strategies to reduce feed cost and improve feed efficiency in livestock genetic improvement programs. The feed intake of poultry not only affects their growth and development but also acts as a key factor that affects feed efficiency. Liver, the most important digestive and metabolic organ in the body, has a critical regulatory role in the feeding behavior of laying hens. However, to date, limited research has been conducted on the effect of the liver on the feed intake of laying hens. In the present study, we used RNA sequencing and liquid chromatography-mass spectrometry to analyze the differential genes and key metabolites in the livers of high-yield laying hens with low and high feed intake levels. The results indicated that the genes TRPM1, SLCO2A1, CFTR, GRIA1, and SLC4A5 as well as the metabolites l-threonine, l-ascorbate, and l-tyrosine were the key factors regulating feed intake in laying hens. Additionally, the measurement of antioxidant activity revealed that low-feed laying hens showed higher antioxidant enzyme activity than high-feed laying hens, which suggests that reducing feed intake does not negatively affect the health of laying hens.