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Central Opioid Control of Feeding Behavior in the White-Crowned Sparrow,
 Zonotrichia leucophrys gambelii
 


Many behavioral responses to stress do not appear to be mediated by glucocorticoids, suggesting another mechanism. We tested the effects of intracerebroventricular administration of beta-endorphin, a neuropeptide implicated in the stress response, on feeding behavior in captive, wild-caught white-crowned sparrows (Zonotrichia leucophrys gambelii). The amount of time spent feeding and the number of feeding bouts were higher after infusion with beta-endorphin than after saline infusion. Beta-endorphin decreased the latency to feed compared with saline. Naloxone, an opioid antagonist, suppressed feeding behavior and increased latency to feed. These results support our hypothesis that neuropeptides associated with stress may initiate adaptive responses to natural stressors in wild species.