水体溶氧量对对虾消化道蛋白酶活力的影响

Effect of Oxygen Content in Water on Proteinase Vitality in Prawn Digestive System

本研究证明，溶氧量对对虾消化道蛋白酶活力确有影响，并有一定的规律。溶氧量──蛋白酶活力散点图表明，溶氧量３．５ｍｇ·Ｌ－１以上时，蛋白酶活力较高，此时溶氧量再提高，而酶活力变化不大；溶氧量１．６ｍｇ·Ｌ－１左右或以下时，蛋白酶活力较低，此时溶氧量再下降，而酶活力变化范围也不大；在２．５～３．５ｍｇ·Ｌ－１范围，溶氧量稍微降低，酶活力便大幅度降低。因此，在养殖生产中，为了维持对虾正常生理状态，有效提高饵料蛋白质的消化利用率，水体溶氧量应该维持在３．５ｍｇ·Ｌ－１以上，防止溶氧量升降波动幅度过大、过频繁和经常出现缺氧状态。

The study showed that the oxygen content disolved in water affect the proteinase vitality in the prawndigestive system and with certain regularities. The oxygen content-proteinase vitality relation expressed in spreadingspots showed that the proteinase vitality was higher when the oxygen content was as high as 3.5mg.L-1. If theoxygen content was higher, the proteinase vitality changed only a little. When the oxygen content was about or justbelow 1.6mg.L-1, the proteinase vality was lower. If the oxygen content got further low, the proteinase vitality alsochanged only a little. When the oxygen content got lower within the range of 2.5～3.5mg.L-1, the proteinase vitalitydecreased very significantly. Therefore, the oxygen content in water should be kept higher than 3.5mg.L-1 andnot changing by large extents and more frequently.