The alkaline protease activity was identified after hatching.Acid protease was not present until the appearance of the gastric gland (about 15 days old).

• 结果表明，大菱鲆初孵仔鱼体内就已具有碱性蛋白酶活性，而酸性蛋白酶活性在15日龄左右胃腺出现时才测得。