All groups are fed with pure mixed diet of AOAC formula for 28 days,the amount of the supplemented calcium in the experimental diet is 0.05%,0.39%,0.45%and 0.88% respectively.

• 各组分别饲以按 AOAC配方的纯合成饲料 ；其中钙分别来自碳酸钙和鳗骨粉 ；其含钙量依次为 0 .；0 5%25、0