Abstract: One-day old chicks were trained in a single-trial passive avoidance task.Based on the performance of memory retention, the chicks were divided into wo groups.AVP levels of the chick brains of each group were measured by using radioilmmunoassay.The results showed the AVP level in the good performance group was significantly lower than that in both the bad performance group and the control group. However, there were no significant differences in the AVP level between the bad performance group and the contrast group.The result suggested that the endogenous AVP might have been consumed in the memory process.

Key words: one-day old chick, memory retention, vasopressin(AVP)