Investigation of metabolic adaptation in developing chicken embryo and post‐hatch chicks by blood metabolomics

This study investigated metabolic differences in chicken embryos and post‐hatch chicks from two egg sizes and broiler breeders of different maternal ages using a metabolomic profiling approach. Eggs from breeders of different ages (32 wk vs 51 wk, 63.2 ± 1.2 g) and eggs of two sizes laid by 45 wk old breeders (55.8 ± 1.2 g vs 67.7 ± 1.1 g) were incubated (n = 9 – 10) under standard conditions. Blood were collected on embryonic (e) days 14, 17, and 20, and on post hatch d1. Blood metabolites were extracted with methanol and derivatizatized prior to analysis by gas chromatography‐mass spectrometry. Compound identification was determined using the Fiehn metabolomics RTL library, and concentrations were calculated using Agilent data analysis software. Pathway and Multivariate data analysis were performed using MetaboAnalyst. Principle component analysis indicated that embryos from different size eggs on both e14 and post hatch d1 clustered separately. By contrast, clustering was not observed in embryos from different age breeders. Pathway analysis revealed differences ( P <0.05) in metabolism involving gluconeogenic and ketogenic amino acids (glutamine, glutamate, threonine, glycine, and serine), linoleic acid, and glycerolipids in embryos of different developmental stages. Conclusively, our results demonstrate that embryo metabolism in later developmental stages differs depending upon breeder age and egg size. Grant Funding Source : Maize grant‐University of Maryland