BACKGROUND: Adenosine has many physiological roles in the brain, and in rodents, it changes food intake when applied centrally. OBJECTIVES: We investigated the effect of central injection of the purine molecule adenosine on both food and fat intakes in neonatal chicks. METHODS: In the first trial, various doses of adenosine (an endogenous P1 receptor agonist), and its synthetic antagonist CGS-15943, were injected intracerebroventricularly (ICV) to the chicks and the cumulative food intake was measured at definite time intervals. The second trial was similar to the first one, only the chicks were fed with a high-fat diet. RESULTS: Adenosine did not affect food or fat intake. Food consumption was increased 30 min after injection of CGS-15943. CGS-15943 also increased fat intake in chicks fed a high-fat diet. CONCLUSIONS: The present study suggests that in the avian central nervous system, P1 receptors are entailed in the regulation of food and fat intake in an antagonistic manner.