Adenosine 5'-monophosphate (5'-AMP), as an adenosine A1 receptor agonist, can induce a decrease in body temperature in mammals. In chicks, peripheral injection of 5'-AMP reduced rectal temperature, and central injection of 8 p-sulfophenyl theophylline (8-SPT, an adenosine A1 receptor antagonist) attenuated the cooling effect of 5'-AMP. In the hypothalamus, 5'-AMP increased the mRNA level of agouti-related protein (AgRP), while 8-SPT inhibited this level. Plasma free fatty acid levels increased in chicks treated with 5'-AMP, while 8-SPT treatment inhibited this increase. Proopiomelanocortin gene expression in the hypothalamus was affected by 8-SPT. However, gene expression of genes related to thermoregulation, such as thyrotropin-releasing hormone, was not affected by 5'-AMP and 8-SPT. Hepatic gene expression related to lipid uptake and metabolism was inhibited by 5'-AMP. However, 5′-AMP upregulated gene expression of coupling proteins. This suggests that birds, like mammals, experience hypothermia induced by adenosine A1 receptors. In conclusion, hypothermia mediated by 5′-AMP via adenosine A1 receptors may affect the central melanocortin system and inhibit liver lipid metabolism in chickens.