Objective To observe the changes of the biological characteristics and hormonal alterations in hypophysectomized immature rats.Method Eighty 4-weeks old Sprague-Dawley young rats underwent hypophysectomy via parapharyngeal approach within two days,and among them 20 qualified operated rats were taken as the group A(experimental group).They were raised together with 20 control rats(group B) under the same conditions.Their body weight,drinking water volume,food intake amount,body length and tail length were re...