Molecular mechanisms of growth depression in broiler chickens (Gallus Gallus domesticus) mediated by immune stress: a hepatic proteome study

BACKGROUND: Immunological stress decreases feed intake, suppresses growth and induces economic losses. However, the underlying molecular mechanism remains unclear. Label-free liquid chromatography and mass spectrometry (LC-MS) proteomics techniques were employed to investigate effects of immune stress on the hepatic proteome changes of Arbor Acres broilers (Gallus Gallus domesticus) challenged with Escherichia coli lipopolysaccharide (LPS). RESULTS: Proteomic analysis indicated that 111 proteins were differentially expressed in the liver of broiler chickens from the immune stress group. Of these, 28 proteins were down-regulated, and 83 proteins were up-regulated in the immune stress group. Enrichment analysis showed that immune stress upregulated the expression of hepatic proteins involved in defense function, amino acid catabolism, ion transport, wound healing, and hormone secretion. Furthermore, immune stress increased valine, leucine and isoleucine degradation pathways. CONCLUSION: The data suggests that growth depression of broiler chickens induced by immune stress is triggered by hepatic proteome alterations, and provides a new insight into the mechanism by which immune challenge impairs poultry production.