Exposure to high environmental temperature is known to negatively affect animal growth. One of the factors has been that heat stress strongly suppresses feeding behavior of animals, the mechanisms remain unknown. Therefore, the aim of the present study was to clarify the brain mechanisms regulating heat stress-induced feeding suppression in neonatal chicks.
Intracerebroventricular administration of corticotropin-releasing hormone (CRH) or arginine vasotocin (AVT) antagonist diminished heat stress-induced suppression of feed intake in neonatal chicks. In addition, heat stress elicited the expression of c-Fos, the index gene of neuronal activation, in the preoptic and paraventricular regions of the hypothalamus. These data suggest that heat stress activates CRH and AVT neurons in the paraventricular region to induce a variety of stress responses such as feeding suppression in the hypothalamus of neonatal chicks.
