Abstract:

【Objective】 The effects of glucocorticoid and tryptophan on the hypothalamic metabolites concentration of broiler chickens were investigated by nuclear magnetic resonance (NMR) in the present study. The aim of the present study was to provide evidences for the understanding of hypothalamic regulation mechanism on appetite and expenditure at stress status. 【Method】 Thirty-two 10-day-old chickens were divided into 4 groups randomly, dexamethasone (DEX, 2.6 mg?kg-1 BW) was injected subcutaneously and tryptophan (500 mg?kg-1 BW) was oral administrated after 3 h fasting, while the control chickens were subjected to saline administration, respectively. Blood and hypothalamus were obtained and hypothalamus extraction was used for NMR analysis. 【Result】 The 1H NMR spectra showed that the relative concentrations of lactate, glucose, ATP, myo-inositol and 3-Hydroxybutyrate were changed by DEX treatment, while tryptophan signal was not significantly altered. 【Conclusion】 The result indicates that NMR could detect the changes in hypothalamic metabolism under stress status. The result suggests that the signals of energy substrates such as ATP and glucose may play a role in the central regulation of appetite of chickens.

Key words: stress, broilers, appetite, tryptophan, hypothalamus, NMR